Celia (agree with Smolder: more of a vote against Yikyik than a vote for Celia, because to me she was in fact that "loathsome little twirp who's only real personality trait was being an unpleasant pest" -- thanks Boogastreehouse for the wording...)

Wizard Guy (I just didn't find Sara Greenhilt interesting, though between her and her husband I can see how the kids turned out the way they did)

Bozzok (again, agree with Boogastreehouse: because it would be a different story with Mr. Rodriguez, though! "Ohmygod! You have a kitty!", so again it is less an endorsement of one character than a chastisement of another)

Sabine (finally, one that I have an actual clear preference due to the character itself -- Sabine is much more interesting than Jephton the Unholy)