Lots of levels with each level being very different, connected through a map a.k.a. Baldur's Gate or Fallout
I prefer lots of variety. I hate the feeling of "seen that, done that".
I prefer a smaller game but with a really epic experience instead of a really big game of constantly encountering the same gfx and gameplay elements.
To put it in console-FPS terms.
In HALO you had the "30-seconds of great fun" every half an hour, which was cool.
But in Gears of War you have "30-second of great fun" every two minutes. (but the playtime is really short, but you just replay the game over and over, because it only consists out of great moments).
If that can be translated to an RPG, there would be a future after all.