I guess the large areas of dark and light kind of compete with each other for me. I think I would crop the top down to just above the red line above the boy's head. I don't think that upper part of the picture is doing a whole lot and this way we would concentrate on looking at the boy.
Our eyes naturally go to the lightest spot of the photo first, so that big empty window area is what we are going to focus on right away and there's not much there to see.
Nice shot of a child's wonderment, though. Good job. :thumbup: