Of the two, Mother Earth is useful albeit less immediately relevant with any appreciable timescale. If she takes a couple of centuries to really kick herself into gear and climb the ladder back up, she'll still be in good stead. We might want to subtly push her worship with farmers anyway, because she might be useful for countering any attempts to cause famine across the Imperium.
Father Storm however we really wanna beef up,
fast. Him and Zathir are our only true shot at contesting control of weather and the sky in general, so that we can use our air force against the Others when they march. If literally all they do for us is stalemate them, and maybe stop literally apocalyptic snowstorms from burying entire areas, that'd be gravy. And Father Sky is a
war god, which we are actually kind of lacking. We have plenty of Gods who are dangerous because of their domains, but really mostly in the right circumstances.
But a God of War is useful for mass combat. Imagine battlefield scale blessing,
@Duesal @Goldfish.
Or hell, just more immediate exercising of powers. We got to see Anu-Simung do the traditional smiting game, and he wasn't even a war god. He was basically Hephaestus.
I'm willing to bet a fully roided up god of storms could blow that out of the park.