My thoughts on realm council are what you said except General resides above marshal which you excluded but he has authority or everyone except ruler as far as military goes especially in times of war. And banker would more of equal to marshal and above dukes in food crises, both real wide or when it only pertains to a single region, though you have a bit more authority when it is one of the duke's regions as he cares more and will thus allow more authority.
Well military has its own hierarchy. I was trying to refer to feudal hierarchy. I consider them separate for the most part.
