New amas

I'm thinking of making the new amas 7'6" long. The present ones are 6'. Rough shape under consideration:

 Solid foam with glass skin. The chine corners would be rounded off. My guess is that there would be about three times the buoyancy in this shape than in the double-ended vee hulls I made, based on the same 10" width and 8" (I think) depth. 

Oh, looking back at it, I see that these are 10" deep, so the final ones could be different. Then again, from the photos of the boat sailing, it looked like the amas could be a bit deeper; 9" or 10".