I hate:
Anomen & Keldorn - "I'm so righteous, pompous and I'm smarter than you!"
Aerie & Viconia - WHINING!
Jan - He has special trait (talks more than every other NPC in the game! Literally!)
Cernd - AC8? Weakling
Minsc - do I have to explain?
Yoshimo - that would be spoiler
I like
Viconia - MR
Korgan - only dwarf in the game IIRC
Mazzy - I just love her!
Wavering:
Valygar - confused
Haer-Dalis - Blades are powerful, but that raven stuff...
Edwin - good caster, bad personality
Jaheira - I don't like NPCs trying to be smarter than me. Who is a godchild here?