I think most companions are great.
I like Astarion. In the beginning his straight forward evilness is an issue, as all he eve approves are the evil acts, bu as his story developes so does his attitude if you play your cards right. To the point where Astarion starts to approve you feeding orphans and some other outrageously good choices. He is an abuse victim who became an abuser himself, but you can either make him realise this or let him become as evil as they go. The guy has some hidden depths and really funny one liners and some shockingly sweet romance scenes if you are willing to get through his hard shell.
I really liked Gale, oth as a decent guy and as an overly ambitious wizard.
I quite like Shadowheart, she was complex, and I liked that even when she was at her worst Shaar fanatic stage she was basically a decent person with a good heart. Her story worked and so did her character.
Karlach is fun. She is a nice and believable person. She is passionate and friendly, someone who cares for her companions and friends. She is a person I would love to meet and know.
Jaheira surprisingly grew on me. I didn�t like her in Last Light, after she made some really dumb comments such as �Oh, now we know that the enemy wants to attack us� or something along the line right after the enemy did attack us. Like, no kidding captain obvious! But later in the game I found that she was quite a funny companion and she did remind me of the original Jaheira.
I didn�t dislike Wyll, I think his rewrite did a world of good to him and I prefer his story over his EA one. That being said he is still just a bit too heroic for me.
The only character I really do dislike is Lae�zel. My issue is not even simply with her personality, because I actually like that and it is in line with what she is. My issue is with her plot and how
everyone from Vlaakith (near omnipotetnt ancient lich queen, to Orpheus, ancient war hero and Giths heir, and Voss) are constantly kissing up to her despite she being on paper an absolutely average githyanki. Then in the end she also proves what a hypocrite she really is and simply lets either Tav, Karlach or even Orpheus to turn into an illithid to save the world, despite all her ranting about saving Orpheus and the githyanki from Vlaakith? She doesn�t even offer to save Orpheus from a fate most githyanki considers worse than death? And Orpheus gives her his blessing? Really?
The only reasonshe is in my team is because I need a tank, ut from now on if I ever play a tank-dps character, she is gointo stay in her cage. Or die a horrble death at the creche. Or by Shadowhart�s hands. I am not picky.