Speaking of sacrifice, I don't see Gandalf's and Dumbledore's sacrifices on the same level (or maybe we're not talking about the same events, me having read HP only once). Gandalf sacrifices himself when facing the Balrog, again when he marches with others to the Black gate. Dumbledore, on the other hand, though finding a gagillion uses for dragon's blood (poor dragons), didn't see the Ring as cursed until it was too late. He then burdens Snape's with his murder/ euthanization and harry with finishing what should be an adult's task.
And regarding King's Cross, being a 'Merican, I know nothing of geography or allusions, but methinks that Rowling was just getting all of those fundamentalist haters back, showing that reading HP was not demonic.
