I specially like the fact that at least twice (I think) Sanzo has been told he is like a young Koumyou, not only in looks but also in temperament

Really? I don't remember that. Where does it say that? That's...very interesting.

And ahaha, yes. When Kami-sama first appeared, I immediately thought that he looked an awful lot like both Sanzo and Koumyou. Interesting that Ukoku picked him, huh? Wonder what that implies.