There is nothing in place for this yet, but we are just about ready to start working on adding this for diagram editor. You will be able to associate property view content with nodes and connections. Should be ready soon.
Regarding similar thing for the form page outline, we haven't had a usecase for that yet. How would that be different than showing content in the details section (right hand side of the editor) when an item is selected in the outline?
I think you've got the key bits listed, so I'm not too worried. And hopefully if you get the basic mechanism in place, it wouldn't be too tough to add to anything else we find needs hooks to the property viewer using the same paradigm.