> I tried to install NIX, but the graphical installer wouldn't boot.
I've had the same issue. Nix uses KDE Plasma by default, which uses a compositor that struggles with some video drivers.
Fortunately, installing from command line is practically the same, especially if you do your partitioning beforehand.
> Then when I tried the text-based install, it couldn't see my NVME disk.
That's a more unique problem. I'm not sure what to do about it either. Did /dev/nvme0n1 just never populate? My best guess is that you booted emulated BIOS instead of UEFI.
Then when I tried the text-based install, it couldn't see my NVME disk.