Yes that sounds awesome, though I'd prefer having a single config file for the window manager, status bar, notifications, application launcher, lock screen and whatever else I forgot that are in the end part of the same experience.
One particular problem is theming: I'd like to set a theme in a single place for all the elements of my desktop environment. Not sure if it's fair to expect a bunch of independent opinionated developers who like to use weird graphics toolkits (when not drawing everything by themselves) to come up with a unified solution.
Another problem is the shortcuts. It's the same problem in (neo)vim when you build your awesome IDE-like setup based on 53 unrelated packages: you end up with an illogical, overlapping soup of keybindings. I think you need someone to take charge of unifying things to provide a coherent experience.
