Really cool seeing how 3-dimensional your gestures look considering that your focus was mainly on representing the 2-dimensional qualities accurately.
It seems like there is often a trade-off between accuracy of measurements and the degree to which the motion of the pose can be captured. I think Prokopenko's gesture drawings demonstrate that you can pull off both: a gesture can capture the proportions of the figure as well as it's motion. However there are many cases where you may want to lean more towards one than another. I think it just depends on what you want to achieve. A fight sequence in a superhero comic doesn't necessarily call for rigidly perfect proportions. It's more important that the impact of the hits and the movement throughout the scene reads. Whereas in a dramatic scene where emotion and facial expression are more important, off proportions would distract and pull the reader out of the scene.
A lot of artists have made the point that you have to master accurate portrayal of a figure before you can convincingly exaggerate and distort it, so I think you're on the right path.