I keep trying to come up with a clearly-defined explanation for why i feel that the HP books don’t compare to many other great fantasy novels, but am not quite managing.
The clearest differenc is that she didn’t really create a new world, in the sense of new concepts etc. – all the details of magic are really old known ones, and she just wove them together (the only real exception that comes to mind are horcruxes). So what ? So maybe its a different escape: You don’t go into a magical world, she brings magic into your world. Hmn…