Filler's Sprites

[Virt]

You seem to have a pretty good grasp on the SS style, but as you said, there could be a little more contrast, primarily on the head/torso/whatever. Besides that, the mouth is a little awkward with the one tooth being lighter and also touching the eye, the pupils may be too wide, the foot overlaps the face a little too much, and the spikes on the head are a little jaggy.