Switching back to Wayland fixed the GUI (for #11 only; I can't speak for the rest of the thread). To do this, I had to add nvidia-drm.modeset=1 to the assignment GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub, then run sudo update-grub and reboot.
Switching back to Wayland fixed the GUI (for #11 only; I can't speak for the rest of the thread). To do this, I had to add nvidia- drm.modeset= 1 to the assignment GRUB_CMDLINE_ LINUX_DEFAULT in /etc/default/grub, then run sudo update-grub and reboot.