Yfelsung said:So you're saying that portraying God as a megalomaniac alien species may not be the best approach?
Though you must admit, making Lucifer/Satan a heroic figure would be some epic trollage if the book got big.
If you write the story. I suggest that you do some research on the specific classes of demons and angels. It would be more fun if you made up stories about them. Ex. The lord of the rings genre. Some christians highly value that series and it has magic, monsters, and otherwise. To me, it's akin to harry potter, hehe. Classes, races, and histories make the game fun to read.
However, I have to warn you. If you don't start writing now, you will never get it done. Studies do tell that if one tells others his personal goal, they tend to never accomplish it.