Muffy! (out of the my current town) I love how the sheep are fat and adorable, how they wear clothes as scarves and just waddle around. ^_^ I do miss Sylvia, she's a close second, I used to have her before I sold my town. But I think uchi is probably my favorite personality. Side note: I also love that they always start singing each time you sell them something or offer to buy something. I don't think I've seen that with any other personality.
Don't currently have one. Tammy is one of the cutest ones but I might like Rocket just a little bit more because she was my first Uchi villager and fits the personality better than Tammy imo.