I feal like there would be more movement in the torso and hips when the character is running. Even when aiming a gun, a character running would have some twists of the torso or the hips. Without this, it kind of looks like he is running towards the viewer instead of were he is aiming.

Also for a singlar frame his lower half juts forward, its a bit jaring, probally want to fix that because it looks like a glitch.