The other stories involving the North American Druids are a bit better. This story seems to lack some of the inspiration those other stories have. In some of the comments you seem to have gotten a bit fed up with fanfiction while writing this story and it shows.
Even if you have given the Brotherhood (immortal wizards) a bigger role than the Druids in this story, neither have really been all that important. Especially the third year at Hogwarts has the good guys doing...basically nothing.
That said, I like the concept behind the Brotherhood. I like the intrigue within the Brotherhood. That one faction is (effectively) behind the rise of Voldemort, while the other faction is fighting against Voldemort.