Can it run non-steam games? I don't have steam FFXIV, nor do I the intention to (if I like a company I prefer to buy from their source). Or perhaps streaming services, if you had like xbox ultimate or what have you.

Could be cool, could be a fancy paperweight. .

Comfortably playing FFXIV on the couch, or some other game, while the wife does another on the TV could be pretty neat.

I want to note, similar to what I said in the CE threads a while back, such a system like valve is using is what I hope FFXIV does in the future for physical concepts. Reselling is a thing and I don't believe it's going to stop anytime soon, in-built systems should be standard practice these days. Naturally you'll have to open the gates, in this example it's only 48 hours.