I have taken the boat out once since the prototype run. We loaded it up with almost a ton of ballast and the new platform worked fine. It's most certainly destined to ONLY be a prototype, as the spray on bedliner is already starting to flake off just from expansion/contraction of being outside in my RV parking.
We might go out tonight with it. Use it until it falls apart I guess! ROFL. We'll be making something more substantial over the winter. The proof of concept is sound, and no reason to adopt any other design.
I did call up TAP Plastics in Portland and they can source me a 62x24" piece of 3/4" HPDE for $188. So, the quickest and easiest would be to grab that, cut off the corners to make my trapazoid shape, round off the edges, and throw some closed cell foam on it for padding and be done.
My buddy kinda wants to go the plywood/fiberflass route because he could make a couple for the price of the 1 HPDE. We'll see what happens though. If we go out tonight, I can try to get some better video.