Did you tried
Gothic 1/2?
These games have a huge fanbase here and i found Gothic 2 quite nice.
Its nor really heavy RPG since you dont have that much choices and you fight most of the time, but nevertheless the gameworld feels alive and it just does a good job in wasting your time.
Neverwinter Nights Gold Edition
Yes, the Singleplayer mostly sucks, but if you dont mind playing in the internet, there are many many different persistent worlds to play at:
From Diablo clone module to heavy RP worlds with a dungeonmaster that creates quests for them, jumps into NPCs so they talk with the party etc.
Or, if you dont like the big Servers, you just look for some " regulars' table" RP groups that meet at a specific time and try to play their own little RP.
farcry
Its an FPS, but not wit the boring Vietnam or WW2 Setting.
Instead, its setting is a big isolated island.
The funny thing in this game is, that is has not a restricted level design as most shooters tend to have but a very open one.
You only have an objective to achieve and the way you do is mostly up to you:
You could sneak to that car with the gatling gun and drive away, or you allure the enemys into the jungle where you can kill them one by one.
Or you sneak to that big watchtower, kill the guey in it silently and then pull out your sniper rifle...
Homeworld
Its an interesting RTS game in space.
But be warned...its really DIFFICULT, for most its even too difficult to be fun.
The key in this game is to defend yourself against the enemy with minimum losses because you take all aour units into the next missions.
So its sometimes a puzzling game where you need to play a mission once just to see what happens and then replay it for receiving optimal results.
Oh and Deus Ex of course
Nice shooter, sure you heard of that game...
Since you dont like turn based strategy games thats almost all i have to offer i guess.
At last i have to admit that i am famous for my love of shitty games...i even think sacred is a great game :D
Oh one more thing, ever played Secret of Mana?
Its an SNES game, i liked it much when i was 12
, but it gained cult status here and since it does not cost anything...