I don't really see the problem you are seeing.

> all of the above tools need to be re-written and adapted to each possible compositor

These sorts of tools have always been (re)implemented by each (moderately large) desktop environment anyway. This doesn't seem like something stemming from Wayland or much of a change in general? Any one of these tools needs to be designed, tested, integrated with the rest of the desktop environment, etc. -- this is where the majority of the development effort would(should?) be going. I don't think the effort required to interface with the window manager / compositor is actually that significant, or significantly higher under Wayland.