I like this. Very nice.
You're keeping Dumbledore's motives hidden; that's good. We don't know if it's the power, or just the game that he likes, but it certainly isn't Harry.
Snape mentions that Dark doesn't mean evil. Does that mean that Light doesn't mean good? That would seem to apply to the headmaster.
I like the fact that you don't have any pairings. There are too few friendship stories. If you must pair, I hope it's Luna and Harry.
I like the looks into Goblin and Werewolf culture. You do a good job.
The friendship between Snape and Charlie was completely unexpected. Actually, Snape _liking_ someone is unexpected.
The letters, too, need a bit more explaination. Why would they wait until close to Harry's sixteenth birthday.
Thanks for writing. I'm looking forward to more.
Tom A.
Author's response
I have been enjoying working with the varying cultures. It makes things more interesting when you are trying to write from a non-human or altered-human perspective. More about the letters in upcoming chapters.