I'm game, but I offer something more to add. You ok with my character being involved in more of a "hungry magic" type of supernatural? It seems complementary to Eldritch horror as it makes some magic seek to gain power and use despite ruining lives and property.

If not, I will go more Lovecraftian Eldritch horror style, Elder Gods slumbering. 

As for angels, demons, lycanthropes, and other beings, you could add them as representatives or byproducts of the eldritch powers that be, thus giving more variety to the powers. It would be curious to see eldritch corrupted "angels" and eldritch corrupted "demons".