Honestly my biggest hope is some generally accepted way to install software that is consistent among distros. I’m leaning toward liking flatpak for this currently, but I also like how appimage works too.
It is really close now, close enough I’ve dropped windows entirely at home, but occasionally there’s still something I’ll stumble across that officially only has Deb or rpm download options and if I try from my distro package manager it fails for one reason or another and I give up, just skip it, and be disappointed for a bit.
Oh and support from devs of games at least as far to get anti-cheat stuff to work via proton, but I avoid a vast majority of those games even on windows because their anti-cheat can be so system invasive…