Admission control proposal

I am starting to look at how I can support some features that will require admission control, so wanted to get high-level agreement on the strategy so I can look to work on some of the more specific use cases we want to use admission control to achieve.

Feedback appreciated.
Summary of which I think are admission control:

1 and 6 definitely.  Probably 4.  Maybe not 2.  Probably not 3, 5.