I'm really surprised you didn't pick up on the whole sorcery thing. It's pretty much what the series is about. It's also pretty clearly stated in the Bible that sorcerers and diviners have no share in the Kingdom of Heaven. So why should I approve of a book series that encourages it?
Now, you could argue that there's magic in LOTR too. And you'd be correct, though not for the reasons you might be thinking of. Let me explain: Gandalf, the elves, Aragorn, and any other protagonistic characters that use supernatural power are drawing their power from God, or, rather, the God-figure, namely, Ilúvatar. Saruman, the Nazgul, Sauron, and any other antagonistic characters that use supernatural power draw their power from the satan-figure, namely, Morgoth. In HP, however, both sides draw their power from the same source. That sounds to me a lot like a white/black magic (that is, the source of supernatural power is ultimately evil, but it sometimes disguises itself as good) thing.
I believe that I addressed both objections 2 and 6.