I don't really dislike anyone.
Riker! Can't stand him. Didn't really like Yar either. But she quit after the first season anyway.
Can't think of any "iconic people" that I dislike. I didn't particularly like Nagus Zek, but he is not what you would call "much loved" or "iconic". I wasn't crazy about Nog, but it would be difficult to imagine the show without him. Jake barely did anything. I was upset when Terry Farrell left and Jadzia was replaced with Ezri. After watching 6 seasons with Jadzia, my heart didn't really welcome Ezri. Keiko annoyed me too.
Kes. Also not iconic though. I don't think I would get rid of anyone though.
Even though a decent character, I'd say Hoshi. Her translating abilities were insane, but not believable. But, again, it would be difficult to imagine the show without her.
Yeah, so pretty much just Riker...