I knew that I wanted to go for a 4 foot by 4 foot square.  This allows for 16×16 3″ squares which is just enough for a lot of simple old school sprites.  Plus, I just think squares look better.   I had to cobble together some additional panels from some smaller pieces of Foam Core I had lying around.  I’m pretty happy with the results.  I also changed the design and added some more white into the mix.  Changing the design took about 30 minutes.