What's stopping your company from hiring one developer to do nothing but code cleanups and submitting them to GitHub? There's nothing centralized about that.
Because cleanups would require very deep reaching changes. If we hired a cleanup dev his #1 task would be "find and remove all magic numbers anywhere in the codebase".
You keep saying you want to get rid of magic numbers, how would you limit the size of blocks? Or would you just have unlimited block sizes?