I don't know if I've necessarily hated any villagers, but there are some I certainly didn't care for that I ended up liking. The first that comes to mind is Gonzo. When I got his Welcome Amiibo card I wasn't sure I wanted it as I'm not collecting to have complete sets, just my favorites. I didn't mind the way he looked, it mostly had to do with his decor and the items you could purchase from his RV. So I ended up selling his card but then later got two more in other packs. I decided to keep one, just because. Then one day I wanted to try out a new villager in my town and decided to give Gonzo a chance. He's been in my town for about 4 months now. Even though I still don't like his decor, his house looks good in the town and I've grown to like him quite a bit!
Edit: Now that I think about it, there is one villager really don't like, even still—Astrid. Snooty villagers on the GC were pretty nasty at times, but eventually could win you over. For some reason, Astrid would just always seem to say all of the nasty comments snooty villagers were known for back then. It also doesn't help that she looks like an evil clown. I can't remember how many times I hit her with a net.
I hated Barold when I had him in my first village, and tried to bully him into leaving, but then I felt kinda bad and decided to give him a chance. Plus... Rasher moved in, and I really hated Rasher. So, I had a new enemy to deal with. I don't necessarily like Barold, but I wouldn't immediately kick him out if he ever ended up in another one of my towns again.
Hmm... All these are probably ones I don't have or never had, but Analouge kind of looks really weird, at least his cart art because I've never seen him in game. I used to hate Dora but now she's pretty cute!