Yeah they are, and BG2 is probably more story-driven than BG but they are still story driven (most rpgs have been for a long time). All I'm saying is you can't wander around the game world without unlocking them first. Now if you're not interested in this world or story then you're unlikely to get immersed and enjoy the experience - that's all I'm saying.
This doesn't explain why I found MotB tolerable than other FR D&D products. Also, I liked the art direction of IWD much more than the cartoonish BGII counterpart. So, the preference of the world setting may play a certain role but it's not just that.
I think there is a difference in "story-driven"-ness or narrativist aspect of BG series and MotB. The stories of BG series are rather linear generic fantasy ones with a few alignment-based choices while MotB allows the players to be more involved in the story development, offering many more role-playing opportunities. With NWN2 OC, I think Obsidian superficially imitated BG series while, with MotB, they analyzed BG series more carefully and employed their techniques traceable to PS:T (PC-NPC interactions), Fallout (Slide-show at the end) and IWD (Combat). The protagonist is still a chosen one but the players can enjoy much more freedom in how the story develops with the special power rather than just following linear good/evil story paths. Of course, the story of BGII is less linear than that of IWD but still very linear for my standard.
BTW, even in MotB, "evil" motivations seem to mainly come from power-gamers' wet-dream. This reminds me of the trading cards of the Witcher somehow, talking of sad geek desires...
I found that the reactions the recruited NPC's (especially Keldorn & Jaheira) had to your actions really enhanced the roleplaying experience and increased the significance of the choices & consequences.
I don't deny that but compared with PS:T and MotB... BGII, indeed, offered more various NPCs if not deep, though. BGII was for me, a king of buffet, where you find almost everything you expect for an AD&D adventure with more-than-average quality (This may be related with what bkrueger pointed out).
Just a small comment:
A single mage is not even close to the most powerful character you can have in BG2. Fully buffed fighter/mages, for example, will utterly destroy most magic based characters.
Anomen was quite strong, too but dual class characters are originally designed for badass NPCs. Also as far as I remember, liches are one of the strongest in the game.
I love BG, but again I don't like any of the Halo games much, find the original HL (and HL2) great but over-rated, and so on ... I think it all goes back to individual choice and preference.
I wouldn't simply point out the subjectivity of tastes without exploring the possible reasonings for different preferences. What is the use of game journalism and discussion boards? Preferences are, of course, subjective but reasonings shouldn't be that subjective. In fact, that's what we are doing when we talk of books, films and even TV shows. Then, why not with games? Also, I found the reaction so far in this thread is much more than something like "You dissed my favorite game and I am angry."