- Games I tried -
SWTOR: One of my favorite "classical tab target" style games. The PvP balance is pretty decent (probably the best out of any game I played). You have standard battlegrounds and arena game modes. Unfortunately, they removed all ranked PvP from the game. There was apparently problems with people wintrading/hacking in ranked so they just decided to remove it altogether. This means that all the "competitive" players have no where to go except regular warzones (battlegrounds) in which they just make premade teams and farm solo and new players. If they added ranked back and banned cheaters this probably would be my top pick. The story/pve is very fun as well. Top contender for "full package" mmo, although the development speed is seemingly much slower than other popular mmos.
Retail WoW (Midnight): The game recently had a new expansion come out and the PvP is a complete mess. It is very obvious that blizzard puts very little priority on PvP development. There is a ton of different types of PvP content you can play like regular battlegrounds, battlegrounds vs bots, ranked battlegrounds, solo queue ranked battlegrounds, 2v2 arena, 3v3 arena, solo queue 3v3 arena, battleground brawl events, and an open world PvP zone. The player base is just not large enough to support all these modes and to add on to that a bunch of them just give terrible or no rewards. The class balance has been extraordinarily bad, there is 40-ish specs and yet in the recent tournament there was like 8 played. I did enjoy the PvE a lot, so its very sad the PvP was so bad.
Classic WoW (MoP): Ranked battlegrounds are dead and arena only has a few hundred active players. Solved meta with heavy sniping/wintrading. Not worth the time to level and gear - quit instantly. I am guessing that the "mainline" classic will be done very soon, as even the amount of people PvEing is very small.
Anniversary WoW (TBC): TBC is definitely the version of WoW that I enjoyed the PvP the most. I did get quite a bit of open world pvp while leveling which was a nice surprise. The normal battlegrounds are tolerable and the 2v2, 3v3, and 5v5 ranked arenas are pretty fun. The meta is solved (although weirdly enough less solved than MoP) which means a lot of people are just playing extremely fotm comps (Rogue/Mage/Healer is like 80% of the high rated ladder). There is also seemingly a massive problem with high rated players selling arena title rewards by "piloting" where they log into the other players account and grind them to high rating. It is hard to consider this a long term choice for pvping as the expansion will pass by pretty quickly. Another downside is the heavy requirement of addons/weakauras, as you are at a massive disadvantage without them and finding and setting them up can take a huge time investment.
FFXIV: Played this for PvE a lot over the years. Unfortunately, the combat did not translate well to PvP for me. Played some of the casual pvp modes (which actually had decent cosmetic rewards which was nice) but never got past that. I have heard the competitive pvp mode was plagued by people using bots/scripts. Update: Apparently there has been some changes to PvP since I played last so this is potentially outdated.
Throne & Liberty: Really enjoyed the PvP in this game. The largescale performance is second to none. The game theoretically has all the PvP content a player could want with largescale siege, battlegrounds, arena, and Guild vs. Guild. Unfortunately the population has fallen off so much that getting any good PvP is very hard. The game struggled a lot with P2W problems, class balance, long required PvE grinds to PvP, and a minor problem of people scripting. There is supposed to be a large expansion coming at some point that could potentially fix these issues? The game has a massive "tech" advantage over every other MMO out, so I hope they can fix the gameplay issues.
Neverwinter: Played this one a lot on launch and really loved the PvP. Tried to return but some combination of graphics, UI, game feel, and weird performance issues made me give up very shortly after starting. Never got to PvP content.
Black Desert: A very hard game to learn, definitely by far the hardest learning curve of any mmo pvp. The game offers large scale siege, guild vs guild and 3v3 solo queue arena. I really enjoyed learning different classes. Siege and the gvg nodewar mode are "Gear capped" so you actually didnt have to grind mobs for 5000 hours first which was nice. The arena mode also uses a separate gearing system so you can just queue it up with no pve gear. For some reason the 3v3 mode has really large breaks between seasons, so if you play just for arena you have really long weird downtimes. The openworld pvp content and battleground mode (RBF) is NOT gear capped so its basically impossible to do unless you have been grinding pve mobs for 2+ years. The largescale is actually very fun but suffers a lot from technical problems. PvP has historically given very terrible rewards, although they seem to be rethinking this recently. I think, on paper, this game has the best systems for PvP but they are extremely unpolished, outdated, bugged, etc. Also, an additional downside is the PvE the game offers is extremely terrible so its very hard to consider this game as a "full package" unless you like spending 8-12 hours a day grinding mobs.
Guild Wars 2: GW2 is famous for its "no gear or level required" competitive pvp. This system was great as you can play any build in the game without grinding levels or gear. The downside to this system is classes and weapons are locked behind expansion purchases. I think I had to pay like ~$150 USD to be able to unlock all the class/weapon combos which is a pretty steep price upfront. Ranked pvp is played 5v5 in small battleground-like maps. I had always heard that the GW2 community was exceptional but in the ranked PvP that community is no where to be found. It was extremely common for people to be raging at eachother, afking matches, wintrading, and intentionally griefing. Also, for some reason you can duo queue the solo ranked mode which causes massive issues at higher rating. There is also extremely aggressive rating decay so if you go away from the game for more than a few days your rating gets destroyed. Queues were always decently fast. There is also largescale World vs. World content where you can either roam by yourself which I did a bit, or join large zerg vs. zerg groups. I know a lot of people really love the WvW mode but for me it was sort of hit or miss. One thing that bothered me a lot was the newest expansion introduced a bunch of new classes that were unimaginably overpowered in PvP (and PvE) and they intentionally waited like 2.5 months to make any changes to them (to get people to buy expansion I guess?)
- Games I did not try -
Elder Scrolls Online: Heard a lot of negative things about the combat systems, so this was very low on my list to try.
OSRS: Played this game several years as PvE-only. I know there is a decently sized PvP community but it did not interest me.