I don't really like the mellowness of the body; the lines are so visible at the joints, which makes him look like a balloon. Just a question Why are the feet different in the example? His shoulders are to broad, and looks like he is shrugging. The line art on the arms could use a little work too; it just seems to get very small when it connects to his body. The hands seem to be curve inwards to the body instead of dangling down. Your main problem is that your pose is forced, it's not just somebody standing there. And maybe a tad more contrast on the lightest colour, hope this comment helps.