I would say paddleboard is more fun and more versatile. Aside from being able to paddle around and explore you can also try to surf the swell/waves if there are any. We even brought a ski toe rope on our last charter and had people "paddleski" behind the boat on light wind days. If it's windy I think it is easier to get blown away on a paddleboard versus a kayak - particularly if you are new to paddleboarding. My wife can attest to that as that almost happened to her at the Bight. Maybe one of each?

Matt