Keep in mind also, there where as many kinds of Paganism as there are types of Christians today, if not more. The gnostic mystery cults in particular where very quick to simply blend whatever local beliefs existed into the outer layers of the cult, making virtually every group slightly different in beliefs and practice.
Some of the pagan gnostic cults of the middle east already followed the sort of god inside line of thought that Ashton and deSitter follow today. They eventually evolved in the gnostic Christian cults and then where stamped out by the literalist Christians, who have never been good at tolerating other lines of thought.
Jay