Good analysis. This is one of my favorite novels by PKD, right up there with A Scanner Darkly and Flow My Tears, The Policeman Said. The guy really had a way with concepts like this that nobody else could quite match, even today. He was a unique one, to be sure, almost like Lovecraft in the way he was so outside the ken of almost everybody else writing in the same time period, and after.

I'd disagree about the whole "calling it a scifi book is a misnomer" thing, though. I think it fits squarely into that category very nicely. Just because something is science fiction or fantasy doesn't mean that it can't deal with deep themes and philosophical questions. But other than that, nice review!