I haven't played this game since launch, but it's been Shana, KYH, and Miyuki for me.
Shana's what I expected. I love the character, and I do like a shoto-esque playstyle, so that was only natural. My only problem is that in a game that highly restrictive in combo routes, Shana has those problems even more so.
KYH is pretty cool, you can play really lame with her. Going into her red form pretty much beats all other options for me because of the buffs it gives. She has a neat teleport followup for one of her specials, but I don't use it too much. There's little need to use it when you can effectively space with her really good range (especially if you pair her up with Kino assist or something).
Miyuki's neat. She gets two airdashes. Pairing that up with her double jump and her air special, you get to stall a bit in the air in certain situations. She has nothing amazing, but she at least has tools. Her super is useful for that hard knockdown too. Been pairing her up with Kuroneko assist since it helps for oki and also covers good space along with 2[C]
Game's not great when you're looking at it through a fighting game stand point, but it's a fun fan service game. It's also nice seeing these characters all drawn by French Bread. I do hope for another update since I like the cast. Even though the game is simple because of the demographic it's aiming towards, I do wish they were allowed to open the game a bit more.