Honestly all of the "it runs badly even on a 4090" stuff is talking about 4K with all the settings maxed - It runs at a solid minimum 30 for me at 1440p on my 3080 at nearly ultra settings. As long as you're not expecting 60FPS at 4K, you can enable RT overdrive on affordable hardware.
Proton may not be perfect but it works for the vast majority of games at this point. And most mod managers can also run through Lutris, curious to hear which ones you've tried that didn't work
I've been playing bg1 on Android lately, anything you would go back and tell yourself if you could? I've basically been flying blind and struggling a bit lol
I personally use and recommend a Prusa i3, which I bought the kit for directly from Prusa for for mine. It's a bit more expensive than something like an ender but strikes the best balance for price to performance and reliability - Not super cheap at $700 but but definitely worth it in my experience from the quality and lack of trouble alone
Tailscale is an overlay network, like a traditional VPN, but with very little config needed to get everything connected. You can use their managed lighthouse and management servers or run your own with Headscale.
Basically you just login to tailscale on all your devices and they get a LAN connection piped over the Internet without opening ports or needing to manage any infrastructure.
There are loads of solutions to that, don't be lazy