I agree with Helm, some un-dithered areas could really improve this. Especially on the skull, you'd expect a few areas to were smoothed down, and they'd certainly make it more interesting to the eye, i reckon.
Wonderful work on the err, lady, as well. I think the uniformly patterned look due to dithering works there, it serves to immitate the grimey overlays used on horror-film posters so often, i think. It's been good to see it progress, as well. Where i thought the woman started out as an anatomically incorrect blob, it works really well now, you really added definition where it was needed. I like the thickness of the stomach-skin, it immediately makes the entire piece more believable.
I'm going to try doing an overpaint of the skull. Depending on how that turns out, i might post it later!
edit:

Just to give you an idea, ofcourse. I also moved the shoulder some, see what you think about it.