I think the pose is good, but the main things that are off about this piece are the colours and textures.
The shirt, for instance, looks tooled instead of hand-pixeled and the creases or oil-spots make no sense when trying to figure out the lighting of the piece. The pants look pillowshaded, where dithering / cell-shading would look more natural and the skin also looks a bit splotchy, more due to the palette than it is a technique-based problem.
What I mean about the colours not working is the fact that everything clashes. The hair doesn't match the skin, which doesn't match the colours used in the pants which in turn clash with the colours in the shirt. Your palette is not harmonious.
One way to fix this is to try and keep your palette as limited as possible and to reuse various colors in different places. A good tutorial on that can be found here. Hope this helps! <img src="e.deviantart.net/emoticons/t/t…" width="40" height="18" alt="" title="Tight Hug"/>