Um. The title of your game implies monotheism, but it’s a supplement for a game that assumes polytheism. I’m confused.
To clarify: I have no problems with people running monotheistic religions in a polytheistic setting. I also have no problem with people running monotheistic DnD campaigns. Do whatever makes you happy. But I do have a strong personal aversion to monotheism, especially to religions that use the g word as a form of address for their deity. And that aversion is strong enough for me to avoid your supplement, based on nothing but its title. So if the supplement is not primarily monotheistic, then I wish you would change the name - and if it is primarily monotheistic, I wish you would make this explicit in the description.
(I don’t care if you call your cat “Cat” or your dog “Dog”, but if you call your god “God”, I feel that you’ve crossed a line, even if you don’t deny the existence of other gods. And yes, I am aware of the etymology of Zeus and Tyr.)