Well, the thing about which I remain unconvinced is if the expansion will even have anything Diagon Alley related. It's quite literally impossible to go from Hogsmeade to Diagon Alley with just a few steps because it would require heavy amounts of apparation, and wizards do not have this ability. We travel through the floo network because there is a fireplace, but there are no public fireplaces in Diagon Alley. That's the main elephant in the room within this whole debate, and unless Jo decides to become extremely lenient, that idea of expansion won't happen.