seeklight is right. Here's is what I would do. I'd make my key light a little more warm as if it's coming from a fire or lights from a town down below the scene. I'd make the fill light coming from the moon the same cool blue-ish color that you have now for the key-light. Right now you don't have any fill light and you're losing all of the details in the shadows. My two cents for what it's worth.