>>43513582You get Erika, Flannery, Viola, and Valerie when playing through the story chapters. There's a few Erika bros that like her, I don't use her personally. Flannery is really useful for her ability to burn. Viola has her uses with trap damage, and Valerie is the best fairy attacker (though that's not saying much because there's only two fairies, an underwhelming type atm).
Falkner, May, Dawn, Lenora, Ghetsis, and Olympia aren't in the game yet. Jasmine will be out later this month. Giovanni is event only so you'd have to wait for a rerun if you want him.
Everyone else you have to roll for but they range between awful and amazing. Sabrina, Phoebe, SS Elesa are top tiers in usefulness.