Villager ideas

I want a place full of pets like cats, dogs, rabbits, etc. Like a pet shop. Which? I dont care about popularity.

that could be good, although the game has more than enough animals in it already so I doubt they would add some form of 'pet' shop in it when the villagers themselves are those types of animals.

That would be cool. I personally would go with rabbits but to get them would be a challenge.

I would love a pet shop with tiny little animals in it - there's a hamster cage or something ingame already, isn't there? But having animals go to a shop where they buy smaller domesticated animals might be kind of weird once it was implemented. I just want to have something running around my house that's not a cockroach tbh.

I have a feeling the OP was asking which kinds of villagers to get in their town for a pet shop theme, not saying they want an in-game pet shop, but I could be misreading it Anyway, I think a good idea would be to have some combination of the following species: birds, cats, dogs, hamsters, and rabbits. Those are all commonly kept as pets. And then a nice idea would be to have them only "natural" colors, for example you can't really find a purple cat or a pink dog in the real world! Some good villagers for this would be:
Cole, Dotty, O'Hare, Ruby, Bonbon, Soleil, Flurry, Hamlet, Hamphrey, Walker, Shep, Portia, Goldie, Butch, Bones, Purrl, Punchy, Merry, Lolly, Kiki, Katt, Sparro, Jitters, and Robin. There are possibly some that I missed as well

To keep a balance of genders and have one of each personality--also based on my personal preference--I'd go with:
Katt
Punchy
Portia or Purrl
Hamphery or Butch
Goldie or Lolly
Jacques
Hamlet
Ruby
Jitters or Sparro
Dotty

That also potentially gives you at least 2 cats, 2 birds, 2 dogs, 2 rabbits and 2 hamsters! Of course, you can modify my list to your own preference, or throw out the whole thing if you just hated it xD But I hope that helps.

When I get my second cartridge I'm gonna make a town full of penguin