One thing that the directional assignments seem to be for is not only ease of channeling, as you suggested, but as a way for us to understand the Gods. The direction one is assigned indicates that, as we learn more about Sorgae, we pay particular attention to what is said about a given direction or God by Their assigned Priest/ess. For example, I was assigned to the North, therefore, my understanding of the North should be taken as a more accurate source of information than that of one assigned to the East. I hope that makes sense *grin*

And, as usual, this is a great post!