I don't think MS will be abandoning UWP because Store apps are the future for Windows 10s which is their answer to Chromebooks. A few tweaks to the Windows 10 UI might be possible, if there is widespread demand for specific changes.
Personally I like the UI, but I think they should concentrate on fixing the bugs and make all their apps consistent before adding new features. Making zero telemetary an option would be desirable too.
As for Windows Mobile, if I'd known there was a WileyFox handset coming I might have bought one. Why didn't TheReg tell us?!