Jolee Bindo was freakin' awesome if you actually got through his backstory and talked to him enough. He HAS to come back IMHO.
HK-47 was just funny. And cool. And strong. I mean, who doesn't love a homocidal assassin droid who calls all non-metallic living things "meatbags"?
Canderous was alright. He can come back.
I never did manage to get to the point where I could do Juhani's quests, so I wouldn't know about her. I'm neutral on her.
I thought Zaalbar's quests on Kashyyyk were interesting, but I never used him as a party member besides that. So I'm neutral on him too.
Carth should come back and then die a horrible, horrible, HORRIBLE death, preferably by tying him up so there's no way he can get out of it and then leaving a gourmet meal and a nice cold glass of a good soda just out of his reach. Then he should be shot in the feet and forced to walk to the food/drink, only to have it pulled out of his reach just as he's about to get to them. Then they should get someone to dress up as Dustil, his son, and say something like "I hate you dad" or something else, just to ruin his mentality.
I'm going through KotOR again as a dark side female 'cause I just found out you can kill him that way if you romance him.
In case you couldn't tell, I don't like Carth.