Mac minis are great deals but I recommend using Linux. I believe Linux will stick long term.
It depends what you want to do.
A mini PC won’t be good if you want to game or host local AI. The new Steam Machine will be good for gaming, but it’s a step short of a full pc. You could probably put a different Linux distro on it though.
You want to ditch windows. Just buy a gaming laptop and put Linux on it