I don't like villagers who are excessively pink such as Fuchsia. I've currently got Renée in my town and I don't like her design at all, gonna get rid of her when I can.
Also not a big fan of villagers who are weird shades of green like Buck. Unless they're a frog or a crocodile or something that makes sense.
As for favourites, I have a few. I love medieval stuff so Sterling and Knox are must haves for me, I love them and have their amiibo cards.
Hans was my neighbour in new leaf, I had him in my town since very early on and I bought the game at release so he's like my best friend, also have his amiibo card and he's moving in soon
Other villagers I'm moving into my town via amiibo are Winnie and Erik, but outside of that I'm looking at getting Ankha as well since Klaus moved in as my first camper and I thought since I'm getting Knox and Sterling I could go for a history set of villagers!
Other than that I love just seeing what villagers I end up with! It's really exciting seeing all the different designs and I love finding out what a villager looks like when they move in. Del is moving into my town as a random move in and I've never seen him before so I'm excited.