Struggling with (Fictional) Religion

I am finding that creating a religion is much harder than any of the world creation or invented history I have been working on.  I want to create a religion which is both unifying and divisive and that can enhance the stories I am telling without overwhelming them.  The religion I am creating is called Daletha.  It is a duotheistic, with a God and a Goddess, as well as a legion of heavenly messengers and saints.  Coming from one mind and in a short period of time, there is no way that its philosophy can attain the complexity over time that a centuries-old religious system encompasses, but I am trying to work out the broad strokes of its theology over time and record its major movements and systems.  Ultimately, it is going to be a transcendent religion, but I am trying to balance that with some descendant theology as well.
 
In some ways creating a religion is a profoundly personal aspect of the world, because it will become a skeleton for the stories I want to write.  If I create a religion whose adherents are not people I would want to write about, I have created a useless construct.  Yet, trying to develop a world-view and philosophical system that fits the characters I create has ended up making me take a close look at my own world-view, and consider the fact that though I am fabricating an imaginary creation it is personally resonant.
 
Scholars examining J. R. R. Tolkien’s cosmology have been quick to point out the ways it fits (or does not fit) his own Catholic faith.  While I have no idea if my (real or fictional) cosmology will ever be studied, I am, at any rate, aware of the assumptions (true and false) which can be drawn.  One of the reasons that Tolkien’s writing is so powerful is the powerful forces underscoring his story, and while he does not have a religion in Middle Earth that we would recognize as such, we do recognize the deep spiritual underpinnings of his work.  It is impossible to say if my writing will ever achieve that depth – I can only hope it will.