As others have said I doubt you will see a difference but I can attest to arch working just fine for gaming. Between steam and Lutris I haven't run into any real issues.
So if you're wanting to try arch go for it with confidence that your gaming experience likely won't be impacted.
I have done 3 and 4, and I definitely prefer the air gradient, it is a nice sleek little box that is flashable with esphome making it tie directly into HASS. Will be getting more of them in the near future.
I dunno, maybe I'm just easy, or got lucky with bugs (not that I ran into none, but none were game breaking) the ending wasn't great but I enjoyed it enough that it didn't spoil the rest of the game. Now it does feel like there is missing content in the final act, and seems like they probably rushed it out at the end, but I spent 100 enjoyable hours getting there so I can't complain too much.
However, I really really hope that either via patches or DLCs they include the missing content and the final act gets polished up to the quality of the rest of the game. Again I didn't think it was bad, just the first two acts were amazing. i will say however one of the best parts of the game is in act 3 as well. Loved the game, almost immediately started a 2nd playthrough, and have plans for a 3rd and 4th.
Yea it hasn't disappointed me so far, I'm also still in the trial, been waiting for a search that turns crap results on G and DDG to try and put it through the paces. Though compared to G it is nice not having half the results be sponsored.