My opinion on that may be colored by the fact that I had a Surface Pro 3, the one place where Windows 8.1 was actually great to use, and taking away some of the focus on tablet use was a regression. Overall you're right though, outside of tablets W10 was an improvement, because 8 tried to stick the tablet UI into desktops.

I was recently connecting to some server with the Windows 8 derived version of Windows Server and gosh that full screen start menu is stupid with a mouse.