Boats with engines don't need to generate lateral resistance as the force from the engine is aligned with the direction of travel.

Sailing boats/kiteboards (unless running square) have a power source pulling at an angle to the direction of travel (most extreme when going upwind) and hence need to create lateral resistance (sideways force) as efficiently (max lift for min drag) as possible. This requires some sort of foil shape with a vertical component (fins or a hydrofoil at an angle).

For this reason the pics you offer won't work for kite racing.

Windsurf race boards have experimented forever with such bottom shaping but always return to simple and minimal combinations of shallow concaves and V with the fin (and centreboard) providing the most efficient lateral resistance.

kitcho207 said..
Good comments DJ.
But why not give it a go.
The pioneers of drag racing beat physics thoughts of the time with forced induction

I have to agree

For a race like the Lighthouse to Leighton beach, 3/4 reach straight line run to the finish line, could be the go. Worth a try anyway.