The book you need to read is Gilbert Murray's; The Five Stages of Greek Religion.

Your concluding comments, that our gods are our ideals, is the basis of our beliefs. It is just that the further people get away from the process of insight and into formalizing prior insights, the more knowledge congeals into belief and religions. Our conceptual tools become the gods of those lacking insight.

For one thing, for the Ancients, there was little distinction between culture and civics, so the political implications of religion were significant. They equated political monotheism with monoculture, as in one people, one rule, one god. Aka, tribalism.

Remember that democracy and republicanism originated in pantheistic societies, as this was analogous to multiculturalism and the multitudes of influences in society.

The Romans adopted Christianity as the Empire solidified and remnants of the Republic were being erased, so it provided that cultural reset.

Vestiges of panteism remained, with the Trinity, which originated from the Greek year gods as a cycling of the seasons. The son reborn in the spring, of the sky god and the earth mother. Which was necessary, given Gnostic Christianity was all about renewal, growth and spirituality. Which then, when co-opted to serve the interests of the state, had to be redefined, especially the notion of regeneration, given the state and the church were to be treated as eternal.

At least until Martin Luther tried to do what Jesus tried with Judaism, push the reset button.

The consequence was the default political system of Europe, for the next 1500 years was monarchy and feudalism. When the West went back to less centralized systems of government, it required the separation of church and state, culture and civics.

The reality is that our philosophic debates over the various issues involved are fairly sophomoric.