Let me compare the small one to the regular small Peach:
Looks alright at least. :P
Anyway, it is very nice to get more playable characters in SMBX. I really like this even know you didn't made peach-4, peach-5 and peach-6 yet. Hope to see those in the future and also have a complete playable to utulize in SMBX. You made a good work.