It wouldn't work with Accession unless they were given to SCH as well (which would still stop RDM's use) and AF3+2 becomes redundant if you just fill it up with a hell load more spells so your entire time is spent enhancing.
That said, it doesn't take away the fact your ideas are still rather good and I'd definitely vote to put them in the game.
PS. Still hopeful SE adds "Enhancing Magic Duration" to RDM's merits.