I've written a satirical book series about an unwitting atheist Norse god, and I think the idea of an atheist god is interesting. I came at it from a sports psychology angle, and Robert, the main character (once he figures out he's a god) only manages to do godly stuff when he completely believes in himself. A god who believes in himself also can't mindlessly believe in prophesies and foretold events. So free will can kill him but it can also save him (and the world), depending on what he believes him. For a creator god, believing is seeing, rather than the other way around. I guess you could say that free will is a part of a powerful, atheist god. 
