If there is power, then God is the most powerful being possible. It’s not just that God is quantitatively omnipotent but, He is the very source of power. Apart from Him, there would be no power to conceive of. He is powerful to a degree that there is no more power that is available for Him to attain. He is so powerful that He is essentially synonymous with power. The same is true of God and any great property. There would be no way to comprehend morality, love, perfection, etc, if God did not exist.
One objection to the preceding point is that the words “great” or “perfect” need to be clarified. It is possible for the words to be perceived in varying ways. Thus, people will have different definitions of God’s greatness or perfection. This once again brings up the distinction between non-theism and theism. Further refining the words great and perfect only make sense after the issue of non-theism vs theism has been settled. Loftus, and atheists in general, are non-theists. There is no reason to even discuss the subject of “which god is more powerful” until non-theism has been eliminated from the pool of live options.