Just a side note, I'm kinda careful about the thought that "people believed X". We know people were highly religious, but BM doesn't deal well with minutea and cultish attitudes, because (shock) not run by millions of people in an aggregational fashion.
Yes, the metaphysics in SA are a little wierd, but we don't have hundreds of philosophers refining it over a millenia to make it seem logical or having to adopt it to local tastes. For me the big thing is that it isn't all "You go your way and I'll go mine." Cultural relativism, or even the idea that foreign religions might have something worthwhile to say is a new concept.
SA is the most german-medieval of the current religions around, IMHO. I just don't particularly enjoy playing within it's sandbox, probably because I really enjoy playing the villian.