I've got 4 characters I've found. Doremi Harukaze
Hana Makihatayama
Onpu Segawa
Aiko Senoo
Notes:
Doremi and Aiko are a bit weak, but they have great combos and magic attacks (That costs magic balls from the lower screen), they also have a fallen object attack that has guard breaking but some how overpowered. When they're knocked down, they get a random boost effect. (Life gauge recovers slightly, pow boosts up, 1+ magic ball)
Onpu has great special melee combos, if you run out of magic ball from the slot, press start while standing still to open her menu, move the cursor down on the word "Magic ball set" and press left and right to fill them up. You can see the command list and learn her technique.
Hana fights like a wrestling champ, her magic rope attack does a bit damage, but her hyper suplex does twice of damage. She also has good counter attacking.
Enjoy.