"In traditional action films, you'd have "three set pieces" in every act (I, II, III) and each would "ramp up" (spend the big money on third set piece)."
Maybe it's a good thing if this changes. Marvel movies have been following this and usually to their detriment, and half the time it feels like the 3rd act big action scene is just thrown in there because it 'needs' to happen. Winter Soldier's climactic scene is by far the worst part of the movie for example.