Welcome to the Dream!
It is nice to see somebody coming interested in Religion! Sit down in our cosy room we have in this section of the library, dedicated to Religion, Cosmology and Myth.
Unfortunately for you, I have to agree with Dek in nearly all points. He has provided you with the links to the existing entries.
I can't think of a tribe right now though, which has not at least a basic outline of gods, but, if you let sit this on your comp for a while, there may be an opportunity at a later time to use it.
As Dek said, it is always good, in every area of the board, to ask, if a certain submission is needed or not.
As we can't use your ideas above right now, what for others do you have which might fit better?