I like it. What I would recommend... Thick lines are probably good, but the smears from erasing, and the arm rubbing against the drawing while being drawn? If you get some tracing paper, You can quickly trace your drawing (so that the lines are neat and there's no smears) press the paper down against a new piece of paper, and use a pencil to rub on the back of the trace sheet. If you do that fairly hard, it'll put the lead on the trace paper onto the new sheet, making the image in a cleaner-cut form.
If I remember correctly, this makes the picture backwards, but that is easily fixed if you don't want him facing the opposite way. If you do the trace, flip the picture over and draw the lines you've just traced on the other side of the paper, and put that down to be rubbed on, it fixes it.
It gives you a chance to eliminate the rub marks and really clean up the lines, if you're interested. If you put up another of this picture, I dunno about signing it though. It'll become an InsaneJournal trademark so the name wouldn't be on the drawing.