BG1NPC is good? Fucking Monteron cost me 4 repetitions provoking the drunkard and his friend at the inn in Beregost also some of the dialogue between Imeon and the PC is kinda kinda teenage oriented[?]. My last nitpick about it is I think it adds the soundset of Imeon from BG2 to the Imeon of BG1 or something.
Not all NPCs are equally good. Some got a more thorough treatment than others.
For extra content I like Kivan, Monty and Xzar. Monty is a real trouble maker, though.
Imoen is annoying, so I tend to ditch her the first chance I get, unless I play some goody twoshoes CHARNAME and use the "canon" party.