I'm another one of those poly-pan people. Isn't a poly-pan a type of squash or something?
I'll take a different tack--not philosophical, but experiential.
If one follows a Jungian type model for a guided meditation, one meets quite a few beings inside one's head, some of which certainly seem to be gods. That, to me, is the polytheistic aspect. If one meets only one God inside one's head ("The still, small voice of God"), then I suppose you'd be a monotheist. However, I think the experience is basically polytheistic, because it's equally possible to encounter God, Lugh, Kwan Yin, or Eris in this way.
Conversely, if one lets one's boundaries down, either through meditative exercises, drugs, or some truly incredible sex, then the entire universe can appear to be basically conscious and benign. So far as I know, this is the experience of the Tao, Buddhist Ground State, The Way, The Truth, and the Light, or whatever name. This is definitely a pantheistic experience, I believe.
I'd also add that the archetypes can be gates to the Tao, just to confuse things further. The Buddhists (and others?) call this Guru Yoga.
So, several different types of meditation, leading to several different perceptions of the divine. Personally, I think that philosophical discussions of why one or another must be true can be...interesting. There's nothing wrong with trying to abstract from one's perceptions to the basic state of the universe, but it would be nice if people first determined that what was going on in their heads had any relevance to the reality around them, first.