I think the chest looks like you're just cutting into the sculpting compound and that's it, so that's why it doesn't look right. If it was sculpted a little better, and didn't look like lines I think it'd look a lot better. Maybe go over it with a dremel sanding head(the one shaped like a cone) to widen the defined muscle area a little or some how get away from "cutting" the area with an exacto blade, or after you do, use something a little thicker to blend it into the actual muscle area:
http://threads.rebelscum.com/showflat.p ... =1#3150742check out that guys stuff, look at his shirtless characters(or partial ones), see how it looks like he makes a line at first, then he slowly smooths the line out to blend into the muscle part? Maybe if you made tiny little discs of the sculpting material and put them on the stomach where the abdominal muscles would be and then slowly smoothed them down to meet the rest of the stomach area, does that make sense?
http://threads.rebelscum.com/showflat.p ... art=1&vc=1In the second link you can really see some progression shots, showing how much you can do when you take the time and work in steps.
Hope that helps, I do have to say the eyes look 100% better, so good job on that, but like the others have said, the chest and stomach area look like he's wearing a shirt with a body printed on it.