
I still think having a single freecad entity to define a local CS, or container like deepsoic calls it, is the way to go. So the extensions as they are now imho seem good. Just the way how they interact with the user must be fleshed out and revised (or better: finished).
This is mostly a ideologic discussion as many people have different ideas on how it should work and how it should be implemented... that makes it super hard to work on it. As you headed already in the thread deepsoic and myself have different conceptions, and even if I'm pretty sure both would work in the end, working together without settling the discussion first is super hard.
So either someone writes down how it should be and alignment is created by discussion, or it will be settled by someone finishing the implementation that is just used afterwards.