I like the idea, a lot actually. Just looking for a few clarifications.

So, essentially, we're playing figures or entities that are often mistaken for Angels of God, who are just people who willed themselves into existing post-death/enlightenment during life? So we're not all ancient, some of us are, and none of us were created by a single figure?

And what is it exactly we can do with Essence? Only one specific thing each Host, or a variety of things, with an overall effect on the Essence around us just by being there, i.e. each Host is capable of warping reality, but depending on their individuality, just being around Mortals cause them to feel and behave a certain way.