Papyrus, except in dry tombs etc., disintegrated. There is one divine entity that could have many representations. Can trace changes through myths and other literature from different periods. Conformity and authority of king and priesthood. Conflict of wills in nature.
Gods play with humans.
Centrality of weather god. Anu as leader emeritus, source of authority. Enlil is power. Men created to serve gods , lowly status in face of natural powers. Serving the gods means temple service, care and feeding of gods, sacrifice.