I like the single material idea too, having done the rubbing strips on my boat from stirrers, I was looking about for things to use them for, I wondered if I could manage to build a small tender for the boat, planked with stirrers.
Thats another project though.
Enjoying watching your cabin cruiser progressing, I was wondering if you were going for any motorisation or rc?
I had a couple of Hobbies outboards years ago, they really benefitted from having the prop blades whittled/sanded to a better profile and the bracing bits mostly removed.