Every other politician in the class story acts like an idiot, I don't know why the ending would be any different. At least you can talk her out of it.
As far as the rank thing goes, eh. It was already straining credulity to have the trooper be promoted to Major, whilst still only commanding a single squad, because they accomplished another mission.
Could be worse. You could be a full admiral but still just captaining a single starship like in Star Trek Online's end-game.