I've been in and out of the HP fandom for years now, and I just recently started reading Harry/Severus stories, including many of the ones you've mentioned. I tend to go opposite of your taste--I like happy endings over angst--and in my search for happy endings with a rather dark ship, I think you missed one part of the snarry dynamic. While the power balance is tipped in Severus' favor, I think a good fic has to have some way to great a power tension, something that gives Harry a separate but equal power over Severus, and many authors do this by giving Harry emotional openess creating a dynamic wherein Severus has physical magical power, but Harry has a more subtle psychological power over Severus. I think Tira Nog's 'A Nick in Time' explores this specifically by creating a relationship where Severus relies upon intelligence and Harry upon emotions. That changes somewhat in 'Growing Pains' as Severus repeatedly remarks upon Harry's casual use of powers most wizards can't comprehend, but I think it serves my point.

Re-reading OOTP with a keener eye on this relationship, I also have to say the portrayal of Harry as firmly idealistic and optimistic about their relationship may not have a canonical base, but I kind of like that characterization anyway.

Enough ranting though. I really liked the divisions you created otherwise, and thought this was very well thought out.

-Morgan