quoted

...
10 -> ~0% used (~100% none)

I think this scale is too specific, I think it would be easier to map
to the one above for the reasons stated there. There would be little
to no benefit to having such small adjustments between 4-10

It's probably best to discuss that once I have something more concrete 
to share :)

I yet have to think about some cases I have in mind, and once I figured 
them out (and had time to do so ...) I'll post something.

-- 
Cheers

David / dhildenb