As an avid sea kayaker, as well as being a long time windsurfing enthusiast and sometimes long board surfer, I am very excited about the world wide interest in Stand Up Paddleboarding. Also having built a C-17 and C-17Light, I like the look of the Kaholo and may consider building one.
However, considering that one of the biggest attractions of SUP boards is their versatility for flat water, ocean, surfing, and windsurfing fun, it seems that the Kaholo with an windsurfing mast box would greatly increase its fun and versatility as well when the wind picks up. It is certainly big enough to carry a wide range of sail sizes for ocean or flat water cruising and with the addition of a properly sized retractable or removable centerboard, should cut up wind nicely.
Anyway, hope you give it some consideration and keep up the great new designs and kits coming.