Uwp (or some evolution of it) is the primary development platform for the upcoming wcos kernel update, so I doubt it will get rid anytime soon.1) get rid of UWP (read- allow mods)
2) bring 360 emulation on PC and give us access to Xbox' BC catalogue.
3) streamline the store + downloader (allow download throttling, allow users to choose install directories)
Basically, make the process as hands-off as possible, and bring backwards compatible Xbox titles on PC (could be part of GamePass). Doesn't take much.
Though, it's already moddable... I can see they making some design changes to make it better though.
2 is allegedly in works, but who knows if they are actually able to deliver it.
Regarding 3, I'm sure it will be improvements but I dunno about letting you chose ant directory. It's a design choice to have the folder owned by the system instead of the user... Though who knows, I can see they being more lenient to have some of their design decisions go in favor of pleasing consumers.