A few posts back I said exactly the same thing God is Existence, His essence (nayture) is existence, and everything exists because it is from Him. That's why evil exists only by our choice, and not by God's will (think about it: absolute Love can not create evil; there is no "room" for evil is somehting that is all love).
I think I can basically agree with this. I know that God is not to blame for any evil, but if evil "exists only by our choice", then how does satan fit in? I would say that satan actively attacks us, fools and tricks us into doing things against our better selves. Maybe I'm splitting hairs on what you mean by "exists".