A real linux installation or darwin-nix? If the former, what steps did you follow? 👀

Same for me, X11 is out of the question simply because it can’t do variable refresh rate on multiple monitors last I checked. And Nvidia and Wayland work together pretty well by now, at least if you are using a GTX card.

Yes, all the environment variables are set automatically and programs respect them.

It sounds like NixOS would solve all your problems. And it makes coffee too!