Well, if you mean customize the Desktop, there are certainly several apps. The first which ocurres me is Rainmeter (FOSS), also Rainlendar(Freemium), and some others. Not a big Problem with this.
I don’t mean the obvious functions and features of Windows, like Xbox, but a lot of apps included, such as the aforementioned eudcedit or the somewhat more well-known GodMode. The problem is that these are very little to nothing documented by MS.
Where I give you the reason is in performance, although at this point Windows has also improved a lot, at least in this aspect I have no complaints at all in W10 (well, at least after removing all the unnecessary services that it brings by default). On Linux it is perhaps somewhat better, but it also depends a lot on the Distro you use, some can also be quite resource hungry.
Regarding stability, I have no complaints since W7 either, Windows is a fairly stable system, even more W10. In old Windows an Appcrash mostly also crashed or blocked the system, not so in last versions. In W10, if an app crash, Windows simply takes you back to the desktop, killing the process, or a Menu appears when an app doesn’t respond, giving you the choice if you want to wait if it finishes responding, or kill the process.