Free Lanes + Watchtower :)
I've been playing vanilla up until lvl120/NG+10.
Got bored repeating the same faction quests for the 10th time, with little variation besides dialogue options. Even that got old.
Terran Armada was huge, like for most people out there. I've really enjoyed the new content. I love Delta, such a capable companion.
Decided to add a couple of popular mods, in addition to the Terran Armada DLC. I added the Trackers Alliance quests, Hells Gate, and most recently Watchtower.
And then it hit me: with this much extra lore, gear and systems, Starfield now feels like what it should have been since the beginning.
I now lead a fleet of 7 ships (including Frontier & Razorleaf, maxed out in upgrades). These two starter ships are actually useful as part of a fleet ! They tear through Watchtower invasions, the feeling is very rewarding.
The fleet system made me go back to ship building and on the hunt for crew. I am finding myself recruiting Mission Specialists at bars across the main planets just to crew my ships. And I'm loving it !
Creation packs adding new lore & quests were generally cool (Trackers Alliance, DOOM, etc) but Watchtower was an OMG moment for me. I've already played through 100+ hours on it and it feels that I can continue to play until the next DLC.
Next on my plate: replace all these Mission Specialists with proper companions, the like of Omari Hassan, Gideon Aker and Amelia Earhart (full list here btw.)