I'd just say that "Andraste and the Maker were all elven Gods and Shartan with them" theory won't come to be, I think. The Maker and the Chantry pretty much cement human religion and faith - they stabilize the world, give people(mostly humans of Thedas) hope and so on and so forth. They're the touchstone of human society: we're told about this as early as DAO, since the game begins with the Chant of Light and the character creator immediately tells us about the Chantry if we chose the human noble origin. Besides, the Chantry seems to be correct about something as fundamental as the First Blight.
To take the absent Maker and the legend about his human bride/prophet away, to say nothing ever happened but a bunch of powerful elven Dreamers getting together - well, that's pretty much destroying the world of Dragon Age. (And mobbing the elves in the process by angry and desperate humans). Short term, it might be good for the drama - hey, look, elves are oppressed! Again! Long term, it's a disaster.
They might go and scare the player a bit, like in that Alienage quest. "There is no Maker. There is no Golden City. But there are demons, yes..." But saying Mythal arranged everything with a little help from old friends who woke up in time for the party? Nope.