Mo, first off, your form looks pretty darn good IMO. You can draw the tell tale link from your draw side elbow to the grip and everything is pretty close to inline.

One thing I would suggest with your bow arm. Rotate your elbow out slightly. It appears to be under rotated slightly. This might help you get your shouldar bottomed out better. Something I've really been working on is back tension, even with a trigger release. I noticed that if I pull pretty hard with my back as I squeeze the shot off, I can feel the pressure building in my grip hand as the bow pulls back into me slightly. When I do this, I drive tacks on the target. If I don't, well, you know.

Oh ya, TFOX is correct, us skinny dudes look worse than it is.