Thank you for giving me the courage to go this route. The only reason I'm on Windows at this point is for gaming. Time to give Proton another try. I can't wait for my Steam Deck to arrive next year! =)
Some games will have issues due largely to drivers. But I stopped booting to my win7 partition at least a year and a half ago, and gaming on steam has only gotten better. Just know that games with anti cheat tend to not work. Lucky for me the only multiplayer game I play much of is Overwatch on lutris. And lutris is still supported enough by blizzard that it won’t trigger a ban by itself.