Of the photos you posted, this shows the best equitation: Your base of support is out of the saddle the correct amount and you are not ahead of his motion. However, it could be improved by lifting your upper body up and away from the neck. The amount of fold in your hip in this photo would be appropriate for a much higher fence.
I find that this particular habit is often the result of stiffness/tenseness in the arm - when you move your hand and arm forward to release, your upper body goes with it because your elbow and shoulder aren't relaxed enough to allow your arm to move completely indepenently. On the flat, practice reaching up toward his ears while in two point, leaving your upper body still. That will give you an idea of how it should feel over fences.
Hope that helps.