Au revoir then.
I admit, with the T2 "teething issues", I'm not too thrilled at updating either.
But I don't have to, so I'm not worrying too much about it.
For Windows, I'd suggest going for one of the remaining "big" vendors and buying from their respective "Business"-stores.
You also get Windows 10 Pro.
Unless you want a gaming-rig - but then, why buy a MacMini?
;-)
AFAIK, Windows 10 still does not come with it's own version of TimeMachine. As with many other things, you need to rely on some 3rd-party software that might or might not work through the various quarterly upgrades of the rolling release otherwise known as "Windows 10".
Maybe CentOS or OpenSuSE + rsnapshot to an external drive might also be a good option...