RE: Float design
I tend to agree with JRF.
The sharp keel at the nose might grab a wave if you have any crab angle going. It would make for a short, splashy landing. I suspect you might also find that the step is a little small, and you could have trouble breaking suction. Also with the changing V-angle all along the bottom, it'll be a lot more difficult to build these than it needs to be. But they DO look really cool.
You >>Could<< make the v-bottom angle constant. For arguement, let's say 20 degrees. Then glue some triangle stock at the outside edge as spray deflectors/chines. It would look almost the same when finished, but be easier to build.