I vote for sheep! I was just thinking the other day I'd like an all sheep town, or maybe a sheep and hamster mix! I just find the sheep villagers really adorable.
I love how short and fluffy they are, it's so cute. I also like that the sheep villagers have such a big personality variety! I'm not sure if you can get every personality (is there a cranky sheep...?) but I feel like you'd get pretty close! And having one wolf would be really cute with the theme, haha. Best of luck with your town!