maybe you could make a character select not baby i said character select like in isaac cain makes more money isaac is based magdelene gets more hearts and keeper gets better shops like the tainted version etc and probably could place your character for free like isaac is better brother bobby etc because i dont play isaac because but anyway what about keeper you ask well it would be chibi keeper and turn chibi keeper into a slower firing three peater
The idea seems to be good, but here you need to think, because a banal improvement in the chances of a good store or heart is not interesting. It would be much better if the gameplay changed for each character in a coordinated way. And if you add, not as much as in Isaac. Because quality is better than quantity.