There are two things which may improve the current published movie. I gave up finishing the test movie, so I'm not so sure if these are practical on the whole, though.
In 1-3, you can warp from the left side to the right side around 3:45.
In 1-4, I slightly changed some actions on the way to the boss room, so he jumped and came close. You can beat him quicker. I think the soldier I rescued is not important for the improvement.