For an atheist, I do find the idea of a all-powerful all-knowing God fascinating. Why does the Universe exist? Because God created it! Why did God create the Universe? He already knows everything, he doesn't lack or need or want anything, he's already perfect as he is. Are we sure that he created only one Universe? Maybe he made several. Maybe he made every possible Universe. Wouldn't that be identical to a natural process creating every possible Universe?