Well, i paly nostale is pretty cool ^^, and Perfect World, i have a friend that play that game she tell me that is amazing.
You can try sword of the new world, this game is great. You may also like to try Lunia, I'm not sure if hacks are still public now but before there was an exploit that allowed you to dupe a lot of items. It's a fun game, you play like a story, from chapter 1 to chapter whatever.
I didn't like Perfect World much; trying to play it gave me headaches. I'd second Visual94, though - I played Ragnarok Online for 2 years and it was a pretty good game. If you don't like the slightly chibi-like graphics in RO1, though, recently RO2 came out (DiviniaRO2, private server) and the graphics have been upped to 3D. (I really liked the game.)
heard of ragnarok? now there's ragnarok II full 3d and everything with lots of things like my favorite SWIMMING you can see terrain and fight stuff underwater.