Actually, the problem with losing leves as you DC would be solved if the leve quest simply remained active when you logged in again. Disconnect with half of the leve done? Log in again with the same half of the leve done. I don't see a way to exploit this, and it didn't take me too long to think of. I have no idea how hard it's gonna be to code it, but I don't really care either, that's SE's problem :p.

-edit-
oh, bob already sort of suggested that