wonderful idea, just a few things... The arm looks like a random kid from below is holding the picture and also a shadow for that lowest B24 wouldnt hurt. Other than that like i said wonderful idea!!!!
Additionally, the lighting on the bombers does not match the photo background or kid. The light source is near side showing highlights the kid's left side of his face while the near side of the bomber is in shadow.
When trying to make something photo realistic, shadows are one of those key points that always needs to be addressed and easy separates obviously fake photos to something more realistic or believable.
And on other note, you may have to apply some filters to both the kid and the bombers to get an accurate light source color. The background imagine is probably taken at dusk when the color of light is in lower Kelvin ranges - Warm White/Orangish White (2700K or lower). While the kid photo is more than likely taken in a studio using artificial lighting in a bright white color range (probably 4100K to 5000K). The Bombers screenshot from Aces High is probably a mid day light source aka bright white like the kid. Both of these do not blend well with the background.
Props on the idea and take my comments as only ways to improve the imagery.
