My only complaint about this is the shadow under the boy. The light source in the photo looks as if it's overcast. The clouds in the sky are all a dim grey and if anything the light is coming from behind the boy. The shadow basically makes it look like the light source should be in front of him, which simply isn't the case. The other part is the shape of the shadow. The length should be determined by how much of the object is engulfed by the light source vertically. If the sun (or light source) was directly in front of the boy, the shadow would be longer, but the sun itself would have to be in full view, with no clouds. Clouds mute the intensity of the sun. If the sun were directly overhead, there would be no shadow. It just seems as if the shadow is coming from out of nowhere. There's just no source of light that really explains the amount of shadow present.

The other thing I noticed was that the shadow wasnt nearly dark enough where the boy is sitting. Based on the actual shadow, the area just around where he is seated should be pitch black. Since it isn't, it really looks as if he was floating above the boards, in a sort of played off perspective where the boards are actually really big, but the camera is far away.

Everything else looks pretty good. But the shadow itself seems to be a pretty big focal point. I would definitely see about playing with it a little, to add the realism. And if you're going to use a shadow, you definitely need to add a light source that makes the shadow at least a little physically possible.

Hope I helped