I use the ublue kinoite-main base image, not one of their very opinionated variants. It is best as a base, better than Fedoras (even though you need to trust Github 100%)
Local stuff in your home is persistent, and /etc is also persistent.
But we are working on that.
Bazzite has a ton of WINE stuff on the system, not really the “immutable small core” principle. At the same time they uninstall Firefox, while Flatpak Firefox does not support all things.
So I recommend to install Fedora Kinoite from the official website and follow the rebase guideline here at the bottom