Miranda,
I also liked the representation displayed in the cylinder seals. They are rather straightforward in their depiction of a hierarchy and display actions that probably took place during the time of their creation. I would also argue in your second example that the helmet Naram-sin wears not only represents his significance and ranking over his soldiers but also the connection kings/rulers have with their deities/gods. It could also be significant that soldiers and fallen enemies are on a similar level to each other!