I setup Plasma Big Screen recently. Added Moonfin, a Jellyfin client that actually works properly with a tv style USB remote. Steam Link runs on Linux just fine, so just add it. Favorite those apps in Big Screen, and you are set. Do the same for any other apps you want. Works with TV remote, game controller, mouse keyboard. Anything you need really.

I disagree with your broad statement that SQL in general isn’t tricky to make more performant if you know what you’re doing. Worked with DBAs who have decades of experience who have gotten great help in streamlining queries and schemas from AI tools in the last couple of years.