Super early on in the game, like release up to about 3-4 months in, the game was actually pretty amazing. The leveling experience was the best in any MMO up to that point, the game was mechanically fluid, the pvp was a lot of fun, the pve was decent enough, and importantly the pvp and pve rewards were both really relevant. Getting rank 60 or whatever it was early on and having your full set of purple pvp gear actually made you pretty beefy - and it mattered. The class design was fucking amazing and fully in line with the SW universe. Not everyone was a Jedi or Sith, and Jedi and Sith were not necessarily the best archetypes to play. Operatives, Snipers, Bounty Hunters etc, were all viable. I don't even remember what was considered like the "bad" class/spec.
Now, the thing that made the game especially fun for me was the class that i picked and played: The juggernaut. Man, hands down, that shit was the most fun class i'd ever played in any game. Coming from playing an Arms warrior in WoW and doing a bunch pvp over the years, Rage Juggernaut was like the dream come true for my playstyle. Holy fucking shit! Just amazing. I reminisce so much about playing that toon - some of the best MMO times ever. Huttball and Alderan maps were my favorite pvp maps of any game of all time.
Aaaaaand then everything went downhill - although it was evident from the start that the game had some glaring flaws and that the foundation was rotten as fuck. Firstly, the game was laggy, almost anywhere. I had built a really good PC just for the game a couple months prior and my shit would stutter all the time. Being in the Sith or Republic hub was like... stutter, stutter, stutter, stutter. The end game was minimal and you could progress through the initial "end game" in a few days. Even replaying the story lines for the story telling would only give you a few days worth of entertainment.
Bioware just took too long to implement new stuff and to fix existing bugs. Which was fucking strange considering they had a huge team involved with the game. The best example was their fixes for Ilum - which was the open world pvp zone. The area was a zerg/lag fest, then an empty zone after their fixes. That's not how you fix stuff, brews.
I tried playing over a couple of tries, a few years later, but the game just seemed to sink more and more. The last time i installed, i played for an hour and uninstalled immediately.
RIP.