>>530474768
Cinderella Gray is really good if you like the sports aspect of uma, not so much if you're in it for the idol shenanigans.
You also mentioned arima which is something I was afraid of as well and I don't think she could've done it in my run without upgraded Nakayam racecourse perk which let her sweep it, if you can't give her that then you really gotta stamina focus her I guess.