reading all them pain points, I had to type this up. free advice, worth what you paid for it.

you know how in life you're supposed to pick your side, your team, and stick to it? like, no tifosi is changing their allegiance because the rival got a fancier kit or a new power forward or whatever; in fact, you'll root harder for your underdog darlings. you don't become a nazi overnight because they're flooding the aether or their spokes is a dead ringer for scarjo. etc.

here, you gotta do the opposite. you gotta anticipate where the major development effort goes to and go there now. you can't cling to X11 and xfce4 and sysv init and whatever and then removed that you can't nicely alt-tab out of games or have functioning HiDPI or you audio stack from 2006 is crapping out and such.

the largest linux hardware manufacturer at present is valve. they went with plasma, they went with wayland, they put in a lot of work to make it better, and with new steam hardware that's likely to continue. in addition, there's a smorgasbord of activity in that sector and that's your best - and I contend, only - bet.

so that's what you'll run, and like it. I've ran close to everything prior to plasma and have occasional nostalgic flashbacks and miss a feature or two over here. but this is the thing with the most hands on and your best bet that someone already solved your issue or is aware of it and working on it.