Thank you!
I was considering making the color palette an unlockable, but it didn't make much sense to me to make players clear the demo to unlock it and to have them clear it again eventually.
Extra characters is something I tried in the original build and I'm not considering doing it again for now. That said, once I get a consistent version of the final product, this could be the first thing I do afterwards.
The artwork gallery is definitely on my list!
And about costumes, well it's very, very complicated when you work with sprites. Unless you have a team of graphic designers, this alone takes hundreds of hours. And I'm working on the game alone ':D
Thanks a lot for the feedback!