The flag in the background is what does it for me. I really like this but would have liked to see more DOF here since the front left stamp is most of the photo but is so out of focus. Good job with this, hope you do well.
may have been more effective to have the larger frame in the foreground in focus as it dominates the shot and takes away from the smaller in focus frame at the back.
4 - Good potential. Criticism; assuming these are all stamps and very small frames, makes this shot likely even more difficult to capture, but I think that more attention paid to focal points, composition and background detail, would have made this better in my opinion.