Vette is my all-time favorite [such a sexy voice...], with Kira being a close-second; I ab-so-fricken-lutely DESPISE Malavai Quinn, reminds me of the type of loser who would wear nail-polish and skinny-jeans IRL, ha ha, honestly though, he just annoys the heck outta me for some reason [as well as the fact that no matter how hard I threw the ****er up against a steel fricken door and force-choked him, he somehow managed to survive, that left me slightly miffed as well...
Also, he's not a companion but G-D-it I WISH HE COULD BE; Lord Praven, from the Jedi Knight story, I absolutely loved how he was a Sith but still had a sense of purpose which he allowed to be governed by his morality and honor [which, in my book, makes him one of the strongest and intelligent Sith out there]; killing a defenseless or weaker foe brought him no honor, so they were allowed to live. I really liked Ashara as well, she was annoying at first, but she grew on me, and I still adore T7, when I walked into the Jedi Temple the first time and he said "T7 = Part of Jedi Order // T7 = Requires Lightsaber Upgrade!" I just about died laughing... And I know I have to throw Mako in here somewhere, just cuz I'm a sucker for the shy girls.
Jaesa, I'm kind of the lunatic fringe here, but after they made her master and quest-line so fricken' interesting, she seemed like a total let-down [also the fact that she goes from Devout Light-Side Jedi to Sex-Starved Maniac at the drop of a dime... honestly though, by the time I got Jaesa, my SW was already head-over-heals for Mission.. er I mean Vette! so Jaesa never got a fair shot] =( And Lieutenant Pierce, I liked, he was the typical Grunt, follow orders, no matter what he feels personally about them.
Aaaand, I'll stop there... :P
Edit -Oh, and I didn't like Kaliyo - at all - but then again, it's not her character I don't like, its more the way she was written, I don't like the 'any-port-in-a-storm' type girls.