Contrast that to BG2. First NPCs we get are :
Jaheira (good), Minsc(good), Korgan(evil) : pretty great.
Viconia(evil), Yoshimo(?good?)), Edwin(evil) : pretty good.
Jan Jansen(good), Imoen(good) : love them or hate them
Nalia(good), Anomen(good) : meeeeh.
Aerie(good): bad.
I pretty much agree with your assessment of the earlier BG2 companions, though there’s not a lot of story for Minsc so I’d put him in “pretty good” rather than great
One could note that Minsc became one of the most popular character, even if he does not have many story elements...
The "banter" / dialogues / reactions between NPCs really add depth and personnality to the characters on top of adding a good dose of believability to the group.
Really hope they'll work on that in BG3 because it's not really satisfying for now and NPCs are pretty much uninterresting outside their personnal quests stuff.
It would be already cool (and maybe enough as it happen quiet often) if they reacted when they "agree/disagree".
Thats said, I also pretty much agree even if I kind of like Nalia (probably the princess-to-be-saved syndrome).