I totally know what you mean D: it became a lot easier for me once I decided to only have cats & rabbits in my town, but if I could, I would fill my town with multiple cats, rabbits, deer, squirrels, and penguins. Btw, Uchis are fairly easy to find since there's so few of them. You should be able to find Mira without too much of a headache, haha. She's in demand, but I also see her offered fairly frequently (or at least I did. I don't know if things are different now).