Discussion for Homebrewed World: creating a Monotheist Church in Pathfinder 2e

Okay, so I'm considering a Homebrewed campaign world that's essentially A Post-Apocalypse "The Magic Came Back" Earth, inspired by Crusader Kings 3's "After the End" fan mod, along with a bit of Thundarr the Barbarian (So I'd add in some Starfinder stuff).

One aspect of CKAtE is that real-world religions do survive into the New Era, but with a lot of changes, along with the addition of new faiths like the Americanists (who revere the Founding Fathers as divine beings).

I'm considering different options, like having separate denominations count as separate "gods."