While I'm not pounding my head on my keyboard on my exams, I'm pounding my head on my keyboard over Icewind Dale 2 and Planescape: Torment. IWD2 has some super-tough battles, let me tell you. Since you're a big fan of battle and magic strategy from BG2, you'll like IWD2. 3rd edition rules aren't that hard to master either. PS:T, on the other hand, has all the roleplaying I wish the BG series had. Just about every conversation and action in that game has impact, and every item has a meaning. It's like Zork.
I don't recommend Fallout 2 or V:tM--they might have been better if they were more fleshed out. Remember, I'm looking at this from a roleplaying perspective.