I personally think God is really Nature itself...
I think labels like "Pantheism" or whatever have really messed up how people think about this (admittedly broad) idea, because classical Christian ideas of God are of an immaterial consciousness that is eternal and outside of space/time. Saying "God is nature" would probably piss off more (especially conservative) Christians than it should, because God would certainly be closer to being "nature" (at least in some sense) than He would be to being something like Zeus.
If anything, God could even somewhat be accurately described as math itself ... in that math would be the "mind of God," and God is classically understood to ONLY be a mind.
The key thing to understand about God in the historical Christian tradition is that He is transcendent, and our minds cannot properly comprehend Him. I would say that it is accurate to call nature or math reflections of God in the sense that they conform themselves to His Nature, but that does not make Him them any more than the reflection of the Moon on a lake is the Moon. In some colloquial sense the term suffices, but nobody shoots a pistol at that reflection and says they put a bullet in the Moon. The tricky part is that pantheists classically do just see God as an emergent property of nature with no proper existence separate from it, and that is where we must part ways with them.
