Sure, personification is an inherent mental tendency, as it's tied in with our social bias. But as soon as Rome adopted Christianity and the Church developed a party line, the whole thing became political. So that provided extra incentive to bury esoteric freedom of thought about God, and to dilute everything for mass consumption.

Plato's philosophy was naturalistic in that it was philosophical rather than overtly theological. He wasn't pushing polytheism, but was naturalizing the gods, turning them into abstractions and elements, and into a unifying force for good. He was depersonalizing the divine.

Aristotle wasn't much of a mystic. I was thinking of his mechanistic conception of the first cause as a kind of magnet, which was again relatively naturalistic, as in philosophical.