Very impressive!
I like the creativity with the Stan Lee.
Aesthetically, I don't like how the burglar's hand encroaches onto the area of the autograph, but it's necessary because that's the theme of the card, the guy trying to get his hands on Stan's signature and Spidey preventing him from doing so.
I also like how you salvaged the Joe DiMaggio...
...although the top of the window on the finished card is still a little too close to the signature for my taste. However, it helps that you added to your post a photo of what you had to work with. I can see that you really couldn't have done any better than what you did.