Once again, thanks for your insighted (does this word exist??) review!
I really can't see what he DID gain by marrying a Faithful?
Well, back when he did it it was just the right manouevre to perform at the right time. He felt that his predecessors had left the Faithful largely unsupervised in the East and that they had grown strong, and his ambitious project consisted in pretending an alliance, "restoring" them to their old honours, and therefore forcing them to spend alternate years in Armenelos and leave family at the capital at all times (this was the system in absolute monarchies of many countries, and for that same reason: to prevent nobles from plotting treason). And, what was even more important: with this appearance of favour, he tore Eärendur away from his followers, who remained in the East.
His marriage to Inzilbêth was a mere pretext, the "facade" to do all this, because political decisions that are taken against a long tradition of contrary decisions must be sealed and justified. And it turned out well enough- but the tragedy of Paranoid Gimilzôr is that there is always something that he cannot control.
Same as for leaving his son with her - I think that Gimilzôr (who is quite young- as a ruler, at least) is, once again, believing that he can control everything, while in fact he cannot. I do not think he would have taken his heir away from his mother at birth, for no reason at all, against custom and tradition, and on plus cause a scandal, but still, the boy was far from being "left" with his mother either: the chapter shows that he spends most of the day with tutors and guardians that his father has chosen, and is just supposed to come and visit her once in a while. That a random tale told to a child could outweight hours and hours of "indoctrination" - this was not so obvious for him at the time. (And I think he was basically right, in a sense: the boy might have mentioned the wrong name and sent all his instinctive alarms flaring, but it´s clear enough throughout the conversation that if there´s something he knows well, it´s still the King´s religion. )
But there I have a question: Why is Melkor "king of Armenelos?"
Because in the religion I am recreating here, the god is deeply connected with the city. This means that he is defined as the "protector" god of a collectivity in opposition to others. He is *not* the god of others, he is the god of the Númenoreans. He may defeat and enslave the gods of other peoples, but he can never establish this relationship of protection with a stranger. If he became "King of the World", it would mean that the Númenoreans do not have any special right to his favour, and this would ruin the relationship between the god and his people. (This is not so weird: it was exactly the same story with the God of Israel. In fact, in Men´s history, universal gods are rather rare.).
As for why Armenelos and not Númenor, you might ask: The main atribute of the god I am recreating is his symbiotic relationship with royalty. He is the King´s divinisation; the King is his representative in the world of mortals and he is the King´s representative in the immortal plane. The fact that he lives in the capital, which is the King´s dwelling-place and centre of power, is just a way to underline this. But there will be a lot more of Melkor in this fic, as you may imagine. :)
Oops - this was way too long. Thanks for your attentive reading, as always!