d'awwww that's lovely! I'm also a big fan of Sweetie Belle. I hope she always stays open to getting a bit dirty and trying new things even if it's outside her comfort zone. It would also make me sad when her voice stops cracking because it's just too cute when it does.
I really like your humans, especially how you don't waste time trying to make a horn look good, and instead be a full human. Fantastic work, she is adorable, I am guessing you are doing Scootaloo next? After that will you do Derpy please? :3