It doesn't seem evil to me. The goal is the raise of BF, and both evil and good actions are necessary. Consider that BF even eliminated a corrupted Octarch

Then, the order is hated and outlawed, because of his positions against the Octarchy and the other gods. But this doesn't make the order evil, just some of his actions can be. It is a secret society, that keeps a huge secret, is obvious that it has to act that way. Also mind that the followers don't do evil for fun, but just to reach their goal. I would consider pure evil, someone that only wants destruction of everything and everyone, which is not the goal of BF (at least, not the one that the followers are told).