I used mo2 from this installer https://github.com/rockerbacon/modorganizer2-linux-installer.
Both on Nvidia and AMD it’s been great. Older version had a bit laggy mo2, but now that is gone. Only issue I have is that ModOrganizer itself needs to be installed to main drive, otherwise it wouldn’t work, but maybe it’s also fixed now.
Manjaro is notorious for getting borked. If you feel you’re able, pure Arch is way better.If you want arch based OS, but with less hassle, I hear endevourOS is good. As for Debian flavour, Linux Mint is a good choice for begginers, many people also stand behind PopOS. Ubuntu used to be the top choice, but people should probably avoid it now, as Cannonical makes some controversial choices.
Good luck!