One of my pet peeves are those players who talk a big game, then either pike the whole quest or who are so ineffectual they may as well be piking - at best you can forget they're even there, at worst their nonstop chatter reminds you constantly of their deadweight. And of course, at the end they insist on broadcasting their revisionist history where their ubertoon was the sole reason for the party's success.
I'm looking at you, chatterbox Ana. Let's have less voicechat and more of this superpower you can't shut up about. And you, Elm, with your pike-all-day-then-adopt-a-condescending-tone ego. I don't care how many times you've been-there-done-that, or how close to godlike you think you are. If you're not pitching in now you're on my squelch list. And you are most definitely NOT the leader of this party. You don't have the star, do you? So quit giving orders.
A few others:
Yewil d'Phiarlan: I know addicts with higher will saves.
All the Bookbinder alts: Always zerging in the wrong direction and finding traps barb-style.
Cyan: Maybe even worse than Elm for claiming credit while doing absolutely nothing to contribute.
Mist: I don't care how well you know the quest. Piking != helping.
And it's not like I'm an elitist. There are a few folks who are total gimps, but I'll always let them in my parties cause they at least try. So props to Mashpaw, Korba, and Benny. And Viercha Ettervs - I'm not sure any of your spells actually landed, but at least you were trying, and you didn't run away from heals.