Ok, so I have a question, and you may address this later.
How will you structurally support the gunwales? Are they beefy enough out of the mold or will you be adding something?
I assume you would make a structure like your tray reinforcment you've done already, but I wasn't sure.
I intend on doing this (maybe with ping pong balls) and the plan for the gunwales have me scratching my head.
BTW, pic with your kid in it is classic.