I assume some of the choreographic stuff that feels like filler are to cover backstage needs: costume changes, moving set pieces into place, etc. So shaving away the padding (a lot of which just feels like padding anyway) might require structural changes both physical and dramatic. There's a certain amount of fan service that could go...there are any number of things that appear solely for the sake of their appearance. Maybe some of the most egregious anti-canonical clutter could go as well. (And what has to stay might grate less if it passes by faster.)
