What do you think of the following idea: creating an UI Library with the PCF framework by using an existing angular/react ui open source library (ex material design). It would be a sort of wrapper on top of an existing UI Framework that would integrate into Dynamics. Thus it could be an alternative for existing Dynamics 365 controls (say you want a "cooler" checkbox/listobx/grid), but could also provide new fancy controls by wrapping the controls from the underlying framework.
I want to start a github project based on PCF + let's say angular material design (just an example) but before doing that I wold like to hear your opininion if that is something that makes sense.