Your time is a limited resource. When you work a full-time job and play Rimworld on the side, the best way to improve your colony's performance is to simply make the game easier to play, so that menial tasks take less of your time. When you're always clicking a million times to manually cut blight, prevent colonists from dying, and find basic information, those are hours that could be spent playing the rest of the game. This is a list of lightweight QOL mods that I personally use to make vanilla Rimworld 1.6 a clearer and faster experience.

The definition of a "Quality-of-Life" mod is one that adds no new content or balance changes to the game, but simply makes it easier to do what's already possible. The goal of this list is to provide you with a bunch of universally useful mods, whether or not you have any interest in changing the content of the game. The first half of this post is 47 strictly-QOL mods, while the second half contains mods that slightly alter game balance or content (but that I'd still recommend to any player). I myself like to use tons of custom content, but everything on this list is in the spirit of vanilla Rimworld exclusively. Let's dive in!

PART 1: Quality of Life Mods

Gold-standard general QOL mods

These mods reduce mouse clicks, and make things more intuitive.

Dynamic Trade Interface
Changes trade windows to be much more intuitive. Creates two separate columns for your items and their items. Sort by price, quantity, and more, as well as filter presets for different types of traders. Essential.
Prioritize Meals over Preserved Foods
This mod makes it default behavior for your pawns to eat perishable meals before touching preserved food. You can already do this by changing food restrictions on the fly, but this simplifies that process. The default order goes Lavish/Fine/Simple meals -> Nutrient Paste -> Berries -> Pemmican -> Packaged Survival Meals. Very useful and saves a lot of fiddling.
Treat Dying First
Adds automatic triage to Rimworld. After a particularly bloody raid, in the base game you have to check every single pawn to determine who's bleeding to death and who has just a scratch, so your colonist doesn't bleed out while your Doctor kisses a boo-boo. This mod does this automatically based on the severity of injuries, reducing the clicking required so you can focus on other issues. However, since Doctors will heal every injury on a pawn before moving on to the next one, it's still a good idea to check in on their progress.
Automatic Stump Chopping
This mod adds three critical tool buttons: "Harvest all fully grown crops in area", "Chop all fully grown trees in area", and "Chop all stumps in area". This saves a lot of clicking and checking of plants. It also allows you to toggle the automatic chopping of stumps whenever your pawns chop down a tree, as well as the ability to automatically apply "cut plants" whenever blight appears on your crops. This is a game-changer for my wrists.
Smarter Constructions
Prevents your pawns from blocking themselves into a corner when constructing walls, even in large groups. So helpful that I can't believe this behavior isn't default in Rimworld.
Smarter Deconstruction and Mining
This mod saves your pawns from roof collapses, intervening whenever they're about to trigger them and removing the roof first before continuing. If the roof is Overhead Mountain (which can't be destroyed) it will simply stop them from doing that and issue an alert. Be warned though: multiple pawns deconstructing the same roof may inadverdantly detach a roof section onto their colleague, so if you're taking out a large roofed area it's still a good idea to use the "Remove Roof Area" zone from vanilla before knocking down the walls.
Better Workbench Management
Adds a number of helpful QOL improvements to workbenches. There's too many to list here but my favorites are auto-opening the bills tab on click, and the ability to copy all bills to another workbench. Not all of the features listed on the modpage work, but there's so much utility in the ones that do.
Personal Doors
Adds the "Assign" button from beds to doors as well, only allowing specific pawns to open them. Keep everyone but Cooks out of the kitchen without changing every single zone, stop colonists/animals from auto-pathing through certain rooms, or make your bedrooms truly private. You can add any number of pawns to each door, but the default behavior is to allow everyone to use them, like normal.
Defensive Positions
You can now set "Defensive Positions" for drafted pawns, making them immediately travel to their spot when you click the Defensive Positions button. Before this mod, whenever a raid hit I would groan. Not because of the imminent destruction of my base, but because I would have to click like a hundred times in order to properly organize my colonists for battle. This simplifies that!
Stabilize Bleeding
Adds the option for your Doctors to "Stabilize Bleeding" on a target pawn, which will patch up only their currently bleeding wounds, leaving the bruises/etc so they can attend to more critically injured patients. Very helpful on the battlefield.
QualityBuilder
Do you only want Excellent-or-higher beds in your base to satisfy your pawns? This mod allows you to designate certain constructions to deconstruct-and-repeat until they reach a certain quality or higher. You will still lose the same amount of resources each time it deconstructs, but it saves you a lot of effort when that's your objective. The default behavior is to allow all construction qualities, so this mod will only trigger when you specifically select an object to follow this behavior.
Davai's Sorted Categories
Adds further sorting of Storage categories in zones/shelves/bills, so that you can quickly identify outliers to the rules you want to set. One example is "Caravan Food", a separate category for Pemmican/Packaged Survival Meals so you don't have to manually track them down. Even better, these items still appear in their original categories (like "Meals") so you can still use the default behavior if you want to. Requires the "XML Extensions" framework, but the Workshop will prompt you to install it when you subscribe.
DragSelect
Lets you drag your mouse over buttons in traders and caravans instead of having to click each one individually. Prevents carpal tunnel.
Smart Speed
Adds an even faster game speed option (usually only accessible in Development Mode). It also lets you customize the speed of each of the four speed buttons, as well as how slowly the game moves during events like raids.
SimpleCameraSetting
A replacement for the popular Camera+ mod, this lets you zoom in and out on the map as far as you desire. It also lets you change zoom speed, zoom range, or make your camera follow a specific pawn around the map.
Keyz' Allow Utilities
A successor to the now-deprecated Allow Tool mod, this provides a bunch of QOL tools such as being able to allow certain items across the entire map, instead of just on your screen. But my most used one by far is the "Haul Urgently" tool. It adds a category called "Haul+" to your job list just after Doctoring/Bed-Rest, which will make the pawns with that job drop everything and haul specific items when you designate them. This does not replace the original Haul tool, and allows you to haul critical items away without needing to change schedules or queue up pawns. If you've ever needed to haul a gun inside after your pawns just harvested 20,000 crops, this will help. You can also create growing zones with only rich soil tiles, among other plants utilities.
Research Tree
Makes the research tab into a Civilization-style tech tree, and allows you to queue up a list of research projects so you don't have to micromanage that. If you don't like the look of the tree, you can disable that feature and use the mod just for the research queue (which is also compatible with most other research GUI mods).

Informative QOL mods

These mods bring important information to the forefront, and add clarity to the game's systems.

Relevant Stats in Description
When selecting something to build in the Architect menu, this mod will display some very useful information in the tooltip. This includes Max HP for walls, Comfort ratings for beds, Beauty for most things, and 'Work required to complete' for everything (plus more!). This information is all accessible in the information menu, but this is immediate, intuitive, and you don't have to lift a finger. Gold standard mod.
Quality Colors
Changes the color of item quality text in all menus and infocards, with a range of colors from Awful to Legendary. Makes it really easy to distinguish item quality at a glance, which is universally useful.
Food Alert
Adds a small bit of text in the lower-right-hand corner that tells you how many days of meals you have left in your colony with your current pawn count. The game does this already when you're at 3 days or less, but this automatically computes it at all times and helps you plan for future harvests, etc.
Letter Permanent Injury
Sends you a notification on the right side of the screen whenever a colonist or animal suffers a permanent injury (such as their arm being cut off). This helps me understand what's going on when these things happen, instead of discovering days later that my pawn just doesn't have a leg. Note: This mod's settings are off by default, so going into Mod Options in the options menu is required to turn them on.
Disease Immunity Progress Tracker
Adds a line graph in the medical tab of each pawn that computes the current rate of infection/immunity gain. This helps you determine when it's safe to change medication types, and gives you peace of mind that a pawn will survive (or die) so you don't have to keep checking it all the time. Every ailment type gets something useful, on top of keeping track of tending history.
BetterInfoCard / BetterInspectCard
BetterInfoCard adds more information to info cards when inspecting items/pawns, as well as the ability to "favorite" certain stats so they are highlighted there for any item of the same class. It also stops the game from being paused when you're viewing the info card (though you can turn this feature off if you like the pausing).
BetterInspectCard extends this ability to the boxes in the lower-left-corner, allowing you to view these stats without clicking the "i" button (such as beauty, sell price, damage, etc.).
Visible Wealth / Visible Raid Points
Visible Wealth adds a little dollar-sign button in the bottom-right-corner, which when clicked will break all of the wealth your colony holds down to the items, buildings, pawns, etc. This is super useful in any Rimworld run, so you can learn what exactly is making the game think you're rich.
Similarly, Visible Raid Points lets you see a breakdown of each raid to illuminate what triggered it and why. Both are great learning resources.
Loading Progress / Load in Background
The former adds a loading bar to the game when it loads up, giving you a time estimate of how long it's going to take based on the last few times it loaded. Gives you an ETA to take a bathroom or tea break before you're sucked into the game. The latter provides the ability to Alt+Tab to other windows while the game loads anything (such as map generation).
Improved Need Indicator
When you hover over a pawn's need bar (i.e. Food), it will give you information on how long it will take for them to receive a debuff if their need is not met. It helps you plan out your schedules and get a feel for how quickly you need to satisfy their needs. Each need bar has multiple degrees of buffs/debuffs depending on how depleted it is.
Who Shot My Leg Off?
When you hover over any scar/permanent injury in the medical tab, it tells you who was to blame and how long ago it happened (which the game already stores, but doesn't display). The base game only shows you this for active injuries, but why not add it to every injury?
Level Up!
Sends an overhead notification (top-left corner) whenever a colonist levels up in a skill. Lets you know how your pawns are progressing without any additional effort.
Show Buildable Material Count
When right-clicking on a building in the Architect menu to change what it'll be made of (i.e. wood), this mod tells you how much of each material you have in storage vs. how much it costs to construct. Very informative and saves you from having to check your stockpiles.
Dubs Performance Analyzer
For starters, it adds an option to display FPS and TPS (ticks per second) in the bottom-right corner, which some players love. But overall, it breaks down how much CPU usage every part of your Rimworld game is using on your computer, from mods to ticks to in-game objects. You can pinpoint exactly what's causing your game to slow down. The best tool there is for analyzing your performance, but it may also just be for the nerds.
Dubs Mint Menus
Increases readability of bills on workbenches, adding icons for the required ingredients among other things. It adds more intuitive menus for actions like assigning pawns to beds, and generally makes menus look prettier.
Dubs Mint Minimap
Adds a minimap in the top-right corner, which is movable and zoomable. It displays colonists as blue dots, enemies as red dots, predators as paws, etc. I can't imagine playing without it anymore. For optional immersion, you can also have it only appear once you build a Comms Console.
Map Preview
Whenever you click on a hex in the world map, it shows you a preview in the top-right of what the terrain looks like from above. Very useful for choosing a starting location, which I always spend a lot of time on. It's borderline not a QOL mod, because it also adds a "re-roll" button which rerolls the seed of just that map tile and shows you a bunch of alternative previews to choose from, which is kind of cheating. But you don't have to use that feature, also this is a single-player game so who cares if you do?
RimHud
A very popular mod that you may already have installed. Adds way more information at a glance in the bottom-left corner when a pawn is selected, including all need bars, food/schedule/medicine assignments, and a selection of relevant skill ratings including their progress to the next level. Some people find it cluttered, but for me it saves me from having to click through menus because nearly everything I want to know is right there. Highly customizable as well.
[LTO] Colony Groups
A huge amount of features, but the most important parts are adding colored mood bars, equipped weapons, and bleeding/sick icons all in the top pawn bar. Those are all critical functions I've grown accustomed to. Also lets you customize how the top bar looks, including size/shape/position, need bars, and more.
RPG Style Inventory Revamped
Adds a beautiful grid-based visual inventory system to the gear tab on pawns. You can easily switch between the full grid, a condensed simple mode, and the vanilla gear tab view. I've never realized how many gear slots colonists have until I installed this mod, and it's very useful for hunting down tattered clothing. Shows you all relevant information at a glance that you'd have to click and scroll for in vanilla. Essential.
Nice Plants Menu
Adds a clean popup menu to the plant selection button in growing zones, sorting plants into a square grid with big pictures of each plant. More importantly, it tells you when the plant will be harvestable if planted today, and calculates an estimate of the total yield of the growing zone (including sell price and how many pawns it will feed per year). It helps a lot with comparing the differences between crops, and for planning out your next harvest. A truly gold-standard mod.

Performance mods for 1.6

These actually make your game run faster.

Slower Pawn Tick Rate
An essential mod if you don't have the greatest computer. Reduces the frequency of non-time-sensitive ticks on pawns by up to 90%, depending on camera distance. Pawns that are not currently on-screen will simply update less. This has no gameplay impact, and does not affect combat or anything time-sensitive. It just makes it so your mood is tracked 6 times per second instead of 60.
MissileGirl
The new RocketMan mod in town. Similarly to the previous mod, it makes specific things like stat checks or comfort checks not calculate on every single tick, but instead every few ticks. It also reduces loading time if you have a lot of mods. It comes with a wide (like, insanely wide) array of options for how to control your performance, but even if you never touch the options menu it is extremely useful to any Rimworld player.
Performance Esmolas
Throttles a number of calculations and synergizes with the previous two mods. It also gathers some older performance mods like Placebo into one package.
Performance Optimizer
Like the previous three mods, adds a bunch of under-the-hood optimizations that don't affect gameplay but improve performance. All four of them synergize together to make your game faster, so I recommend installing them all!
Smaller Planet
If you have a slower PC and generating/viewing the world map makes everything sluggish, this mod simply reduces the size of the planet. By default, it generates planet with only 10% the number of tiles as the default world, which has over 600,000 hexes by default. This is often enough to significantly boost performance, and it allowed me to actually use 100% coverage of the sphere on my laptop when I used to always play 30% coverage. You can customize the radius value by editing the mod's sole .xml file, but as-is it's a great improvement.

Essential visual improvements

I can't imagine playing without these, and all of them should be official additions.

Seamless Doors
This automatically adds a 50/50 dividing line between two floor textures underneath doorways. So if your hallway is one floor and your bedroom is another, it looks seamless!
Graphic Chair Overhaul 2
Your pawns now look like they're actually sitting in chairs instead of just hovering on top of them.
Show Me Your Hands
Adds cute little hands to your pawns when they're holding a weapon in front of them.
Damage Indicators
Adds little floating numbers whenever something takes damage. Like it's RuneScape.
BetterScrollBars
Simply changes the scroll bars to be thicker and fit the Rimworld aesthetic.

PART 2: Great non-QOL mods for the Vanilla player

Common-sense, no-brainer balance changes

These mods bring Rimworld a little bit closer to reality. Of course, that's just my opinion.

Food Poisoning Stack Fix
I didn't realize that the default behavior in the vanilla game was to potentially taint an entire stack of 10 meals when a single one with food poisoning is added. This mod tracks the number of meals created with food poisoning per item stack, ensuring that the amount of vomiting is consistent with the indiscretions of your Cook pawns.
Dress for the Weather
Have you ever played on a very cold/hot starting position and had nearly every raider and trader flee (due to dangerous temperature) before they even reached your base's walls? No longer. Now, any pawn visitors will enter the map wearing appropriate clothing for the current weather, including raiders. It levels the playing field, though the game will be a bit slower for a few seconds when visitor events are triggered (the pawns need to get dressed).
Allow Dead Animals
Automatically allows fresh animal corpses on the map when they are killed by predators, and/or sends an overhead notification when this occurs. It does allow you to auto-haul in more meat than just hunting, but IMO it simply makes the process faster since I'm often looking around the map for fresh kills anyway.
More Trait Slots
Adds additional traits to pawns when they're generated, with the minimum and maximum number to add in being customizable. To me traits are one of the most fun parts of the game, so why limit it to just 3?
Common Sense + Opportunistic Cleaning Patch
Adds a ton of toggleable tweaks that I agree with, the most important one being that pawns will clean Kitchens and Hospitals before working in them. But also includes other helpful pawn behavior like prioritizing ingredients/meals/medicine that will spoil the soonest.

And here's a rapid-fire list of more no-brainer balance tweaks, the names basically describe what they do:
No Burn Metal
Filth Vanishes with Rain and Time
Beautiful Outdoors
Door Clearance
Settlement Inventory
Ugly Together
Sensible Bed Ownership
Forced Rearmament
Mining Priority
Stonecutting Extended
All Production Gives XP
Social Experience from Trade
Allies are Helpful
Animals are Fun
Floors are Worthless
Functional Room - Makes room size ignore furniture.
Not My Fault - Removes reputation penalty from visitors dying to predators, raiders, etc.
Just Put It Over There - Traders will drop off your purchased items in stockpile zones if it's convenient.
Craft With Color - Dye clothes with Tinctoria when making bills at the tailoring bench.
Meals on Wheels - Lets colonists grab meals from each other or caravan animals.
Almost There! - Stops caravans from resting if they're <4 hours from their destination.
Ugh You Got Me - Social-fighting colonists stop when one of them gets badly hurt, unless they have violent traits.

Subtle amounts of new content

Replace Stuff
This lets you draw walls directly over any object, including doors, buildings, and even rock walls. It keeps roofs and wall lights installed when replacing tiles. It also allows you to replace any workbench or bed with a different material of that building type, and it will maintain all of the bills and bed assignments so you don't have to set them again.
However, this is a content mod for two reasons:
i. Apart from mining, it waits to actually deconstruct the original tile until the moment the new construction is finished, doing an immediate replacement that preserves the air inside freezers and the heat inside rooms. That's something you just can't do in the base game. Additionally, it actually takes less work to replace a wall than to build a new one from scratch, which changes the game balance for construction.
ii. It adds an "over-wall" vent and cooler object to the game which let you ventilate air through walls that are 1 or 2 tiles thick, as an alternative to the vanilla air vent/cooler. Useful, but not QOL.
Optimization: Meats / Optimization: Leathers
Optimization: Meats is an essential fix for me, since all animal meats have the exact same properties, they just can't be stored together. This mod just condenses them into a single stackable item type for your freezers. However if you have the Ideology DLC, it makes it challenging to do "Venerated Animal: Cow" since all animal meat is now considered cow meat, and your colonists will get a mood debuff for eating it.
Optimization: Leathers does the same thing but condenses animal leather into 9 categories like Birdskin and Lizardskin, depending on their source. I still use it 100% of the time, but I have to admit there's a certain swag to a colonist wearing a "Panthera Fur Duster".
Livestock Traders
Adds a type of trader that buys and sells live animals. Lets you tame a wider variety of creatures than those that appear in your biome, and makes farming animals even more powerful than it already is. Might make the game too easy, but lets you experience more of the wildlife of the game (especially if you add any animal mods).
Geological Landforms
One of my favorite mods ever. Adds 43 unique landforms that are strewn across the globe when you generate your planet, such as Canyons, Atolls, and Craters. Also allows you to settle on impassable Mountain tiles, and makes island tiles into real islands. It adds so much spice to the game without adding a single object, all it does is change the shape of the terrain. 10/10.

Salt-to-taste visual and QOL mods

Simple Blinking Animation
I don't like most animation mods, but this one is subtle and makes your pawns feel more alive. They will blink every few seconds, and close their eyes when they sleep.
Soil Contrast
Makes stony soil brighter and rich soil darker, so that it's easier to discern them.
Muzzle Flash
Adds muzzle flash to guns whenever they fire, which is a very intuitive visual marker during combat.
Sense of Depth for Tall Buildings
Similar to Graphic Chair Overhaul 2, this draws pawns behind tall buildings like Steles as long as they are north of them.
Pawn Name Variety
Takes each predefined first and last name in the game and randomizes them during pawn creation so you don't keep seeing the same names in every game. Does not affect enemy faction pawns if they have specific naming conventions.
Dubs Apparel Tweaks
Has options for displaying hair under hats, and taking off coats & hats while indoors. Apparently this doesn't work for some mods, though.
Quality of Building
Applies textures to vanilla buildings, apparel, and weapons based on their quality designation. Awful quality is shabby-looking, Legendary quality is pristine, etc.
Wing's Meaningful Parties
Doesn't change the frequency of parties, but whenever pawns throw them, they commemorate a specific event that happened in the past, or that just happened that day (there's always an excuse to throw a party!). A lot of fun flavor without altering game balance like most party mods.
Knick Knacks
Your pawns add tiny (un-interactable) personal objects over time to bedroom and dining room tables, like picture frames and silverware. Just cute!
No Default Shelf Storage / No Default Gather Spot / Disable Automatically Selected Travel Supplies
Three QOL mods that disable the game's default settings for shelves, tables, and caravan supplies. I prefer them all this way, but some people find those features helpful.
Pharmacist: Represcribed / Pharmacist Icon
Allows you to set different types of medication to be used for different severities of injuries. For example, you could have your Doctors use no medicine on bruises, herbal medicine on cuts, industrial medicine on infections, and glitterworld medicine on surgeries. Adds a new tab to the bottom bar (or just an icon with Pharmacist icon) which can be annoying, but it is a useful bit of QOL.
WeaponStats
Adds a new "Armaments" tab to the bottom bar that displays sortable lists of ranged, melee, and thrown weapons (and apparel) and their relevant combat stats. You can sort your guns by DPS for example, which is always useful and quite annoying to find in-game.
In general, if you find that your bottom bar has become too cluttered by adding mods, nearly every extra button added by a mod can be hidden in the mod options, so that there's less space taken up for things you won't use often. WeaponStats and Pharmacist are the only mods in this post that require their own buttons, so maybe don't install them if you're feeling overwhelmed.
Better Architect Menu
An overhaul of the vanilla Architect menu that becomes essential if you're using lots of content mods. But for the vanilla game, it may just be too drastic of a GUI change for little benefit so it's understandable that you may not want it.

DLC-specific mods

What's That Mod / Consistent Text
Two essential QOL mods if you have any DLC or content mods installed. What's That Mod clearly identifies the source of every object/pawn/etc. in the game in their descriptions. Consistent Text properly capitalizes and standardizes as much text as it can find, for a more unified experience.
Ideology: Keep Converting
QOL Mod. The Moral Guide has an ability to Convert another pawn which is on a 3-day cooldown. This mod adds a button to automatically re-trigger this job on a target pawn whenever the ability comes off cooldown, stopping the cycle once the target is fully converted to the new ideoligion.
Ideology: Custom Prisoner Interactions
QOL Mod. Adds a lot of additional options for prisoner/warden behavior, including things like "Reduce resistance, Convert, then Recruit" or "Convert, then Release". Makes it so you don't have to keep monitoring your prisoners to achieve the fate you've chosen for them.
Ideology: Useful Terror
Terror objects in Ideology don't affect slaves at all once they have the collar and body strap equipped, making Skullspikes and other objects basically useless. This makes them useful again, and the balance is tweakable in mod options.
Ideology: Self Dyeing
Allows pawns to dye their own clothing at Styling Stations, if you let them. Helps streamline the favorite color feature, and gives your pawns their own immediate identity.
Biotech: Childrens Drawings
Adds 70 more potential floordrawings for your children, instead of only the 4(!) that come with the DLC.
Biotech: Growth Moments Make Sense Now
Biotech babies have a higher chance to inherit their parent's traits and passions during growth moments, instead of just being random.
Biotech: Consistent Gene Inheritance
By default, Biotech's gene inheritance system basically discourages breeding between parents of different xenotypes. Which genes get passed down is arbitrary, unintuitive, and inconsistent, and it's basically always worse which doesn't feel good. This mod simplifies the system so that all genes have a 50% chance of being passed down, which is how it works for parents of the same xenotype.
Odyssey: Letter Gravship Ready
QOL mod. Notifies you when you can take off again. Really nice for nomadic runs.
Odyssey: Gravship Biofuel Refinery Retexture
Makes biofuel refineries (a mainstay on Gravships) blend in with the rest of the buildings.

Many of the mods in this post use Harmony, so make sure you have that installed too. Also, I cannot recommend RimSort enough, it will automatically sort your mods for you in the correct order. You can save different modlists for different types of runs, and switch them whenever you want. It also works as a launcher for the game (I use it every time) but you could just use it once and then open Rimworld the normal way from then on.

Reminder: Always back up your save file before adding/removing mods, just in case.

Thank you for reading! Please suggest in the comments any other QOL mods for 1.6 that people should know about.

u/Icy-Perspective-117