Fish works fine as a login shell. If you’re worried, you can create a temporary new user with fish as a login shell and test it before switching your current one.

I don’t have nvidia hardware, but 15 years ago the proper way to setup the drivers on fedora was via rpmfusion.

Does it have to be supported in wlroots/composers, or are these changes in wayland enough? Edit: nevermind, the pr links other prs, such as https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4262

No experience, but they’ve been working on rekordbox support for a while, as well as few others