Ok, allow me to completely over-analyse this:
The art style is really well done, the 3D effect is quite convincing. However, there are two flaws in this that are bothering me. (1), Vader is just standing there, the suspense and drama would be greatly improved if he was cutting up some more Rebels (or providing some sense of urgency/drama.)
And (2), the face of the soldier is missed at a first glance by the distracting (and coloured) figure of Vader in the background. Your eyes really flick towards him, and away from the incredibly dramatic face that sells the scene. If the lighting on the Rebel's face was brighter or starker in some way, that might improve it.
However, the art style is amazing and proportions are perfect. I truly envy the skill that has gone in to this. 7.5/10.