The best description of God that I can think of is the rules of how our reality works.. The principals of natural law is and always has been the proof of the existence of God.
The funny thing however is that "I AM ALL THAT I AM" , I AM THAT I AM does not have the meaning that you have ascribed to it. At least I don't think it does.
The thing about the phrase is that one cannot even read it without recognizing I, or the is-ness of am. Our ego is the illusion is a good way to see it as far as I think anyway.
Nice food for thought post.
yes, ye are GOD.
A part of the first cause.