Those look pretty good. My floats are 38" long, and are a bit too large for the Superstar, although the water handling is superb.

I would make them at least 4" in beam, and don't worry about the V bottom: it's true they land a little smoother, but they also have more drag and are harder to get on plane than flat bottoms.

I think I would sheet the foam with 1/16" balsa (using contact cement) instead of glass. Glass doesn't really add any strength.