I haven't played the game enough to tell you who I don't like, but I will say that you might find Jaheira a bit less of a bitch if you take her with you in BG2. She has some quests and the like later, as well as a romance, where she shows her nice side.

I play female characters, generally. I've played a bit of the game when I dragged Jaheira along with me, and I could not stand her at all.

Jaheira is awsome -as a friend to my Player Character. She's not everyone's cup of tea as a romance interest. And as a party member she's awsome b/c she gets along well enough with everyone, is a good fighter, and her spells are very effective. The storylines regarding her in BG2 are also very intriguing.

In BG1, I despise Edwin, Eldoth, and Faldorn. And I find Branwen to be clueless.
In BG2, I despise Edwin as usual, and also Haer'dalis.

Anomen and Nalia are the most annoying.

Viconia is a real bitch, Jaheira keeps nagging and Aerie is a whining wimp. In fact, all the possible "romance interest" characters are annoying in BGII.

But I do get along with all of them.

Minsc...

*hides behind rock*

I jest. I find Khalid a pain. Especially Imoen.

I don't understand why everyone hates Imoen. What's so annoying about her?

The only one I dislike is Tiax and his whining megalomania. All others are just fine to me, even the often dispised Anomen and Aerie (you have to see through some faults of people, both are very useful in a party). And it's nice to see Aerie picking up courage and love for life because of my PC, even though the relationship doesn't feel equal, because of that.

Minsc. He's just a one-dimensional joke without depth.

Hating Minsc is like hating Homer Simpson or Han Solo. You are no human, I guess.

Me big strong brain-damaged skinhead. You like me or you no human.

Its her voice actor more than anything. As a character shes not too bad. I find Khalid annoying because no fighter should be such a whimp. However his stats say it all.

Imoen, Imoen, Imoen and Imoen.

The problem with Minsc in BG2 is his voice; way too over the top compared to BG1 and therefore annoying. I usually don't take Jaheira either. But I do love Imoen in BG2. The most annoying character to me, however, is that turnip-loving gnome.

Imoen, Aerie and Nalia, in no particular order. Anomen isn't much behind them either.