I agree that the large dithered areas aren't doing much for the picture's general look. I'd also rework the lines especially on the left arm (as seen from our view) because they read as a bit squiggly currently. Maybe try tilting the angles a bit if it can make the lines cleaner and you don't want to AA for smoothness.
Lastly I'm not a huge fan of the foot. The 'calve'-area looks pretty uninspired, and the details mostly looks like bumps in the metal. I'd go for something more sectioned and chunky.
The "mouth" is really neat though.
EDIT: Ah, sorry, didn't see the reference picture at first, I thought it was your own redesign... Well, then nevermind my ideas on the feet; you're just gonna have a hard time translating the venty texture to pixels. If you look at the reference picture though, you'll see that the texture is mostly just highligted lines. Try going for the same color combo and you might end up with a less wrinkly look. :O
