I didn't really move too far from the tutorial so I'll most likely go back and do something a little different with these same concepts. Overall, I'm happy with my result, though I wish I could have done more with compositing. My computer tends to slow up whenever I introduce blur nodes so using the blender compositor gets a little slow.
One thing I was curious about was the numbering on the boxes. On all of the references I saw, the numbering on the mailboxes was very prominent, so I think it would add to the realism of the piece if that element could be added. My question is if that would be easy to do or a major pain? I can't think of a way to create the numbering without a lot of extra work so, I'm wondering if anyone has a better idea.