Can we be told a little more about Illaoi's faith?

It's hard to understand it all. If Illaoi believes only weak gods demand worship, then why have a temple if not to pray in and observe scriptures? Qupting from her lore, "Lesser priestesses are tasked with maintaining temples, calling holy serpents, and teaching people the ways of Nagakabouros." I remember reading somewhere that the Isles are also polytheistic, I think, and that Nagakabouros is just the chief-most deity. Is that true? What gender is Nagakabouros typically referred to anyway? I know "A god's appearance is limited only by those observing it", but how do they refer to 'Kabouros for simplicity's sake? Is hers a matriarchal culture? She does assume Randuin was a priestess, and says "Sterak? It is the fury of the mother I will bring."

So many questions.