There's numerous characters that can create stuff from thin air. You can't compare power levels across franchises that are very different from one another (Superman vs Goku type stuff barely works).
Maxwell's powers are limited by what he can describe with written language and the speed at which Maxwell can do so. Q's powers are effectively similar but seemingly without either limitation.
If God existed, I kinda imagine he'd be like end-game Dr. Manhattan. Which was probably the message, but explained really well through the journey.
But, OTOH, if God did exist, it'd have infinite capacity to have infinite care and consideration for every quark. Unlike Dr. Manhatten, it could just choose to care, choose to limit the effects of being omniscient. Dr. Manhattan was as much a victim of his powers and, obviously, unable or unwilling to control their effects on him. He could fork off instances of himself, but he couldn't resist the ennui of inevitability. He was a puppet of fate, and was aware of that. By definition, God is omnipotent, and therefore would be unbound by those limitations.
Alan Wake seems to command reality far more profoundly than Maxwell, though “Alan’s” powers come with a caveat; His writing needs to make for a gripping story.