If I might suggest one thing: The main difference I’m seeing (I think) is that SB’s body (head+torso) isn’t quite moving as much as in the original. If you look at the animation you’re basing this off of, it looks like her body shifts from its rest position to 4 other positions where she’s leaning forward (at least slightly) and/or tilting her head upward (and rotating her head so it switches between aiming forward, to her left, and somewhere in between). If you add that in, the animation will probably feel a bit closer to the original.

its so static in some places, some of the bones look to only be animated at certain times, not a good idea if you want to keep it canny, also for the love of god, does the rig you use not have any inverse kinematics? the feel clip through the floor at least twice, shit should not happen.
 
Like your previous animations, you are just not putting enough weight, thought or quite frankly effort into the animations, a starter-animator could make this in 20 minutes or less, really google some of the techniques of animation.