The only thing worth saving from windows8-10 is the windows border. it is a huge usability win. Clear borders. square (so it's also fast). clear colors showing which window has focus. It's also funny this show up now a day after the top post was the osx windows border radius fiasco.
yet no linux WM has a decent windows8-10 window border clone.
KDE used to but since the rewrite of the theme from kde5+ they not only killed it, but also removed the option to have sane window border color to show focus. Now it's "accent color" which should be non contrast because they will force that same color on toolbars and such, just like all the bad ideas from office-ribbon era.