Greg,
Great work. I really like how you handled both the front and rear supports. Looks like things should still be plenty serviceable for fishing. If a fish runs hard from port to starboard, you might have to pass the rod around the rear supports but that looks managable. Most of the time though, the rear supports are completely out of the way - nice!
With the present configuration, where does rain the hits the top run to? Do you have it tiltle a little forward or aft?
Also, I assume that the choice of the side support rails (e.g. with holes) is so that later you can hang other things (like perhaps canvas or maybe even a hammock) from the underside. It's difficult to tell from the photos how much weight those rails/holes would support but I could see a lot of potential uses for them if the can hold significant weight:
1) The aforementioned hammock idea - I could see lazin' suspended back there.
2) A boom for pulling crab pots.
3) A place to attach a canvas canopy
4) Hangers for spare lines, fishing poles, etc (injun candy?)
I'm sure you have many more ideas, but I like what you've done! Also, I agree that there are many of us (including me) who would like to buy such a beast if you ever decide to go into "production".
Best,
Roger