So what construction would you recommend for the type of kayaks I have pictured as a minimum? Not designed to run down rocky rivers, just to surf on waves but be able to take a scrape or two coming into the beach?

Kite boarding is a completely different situation to kayak construction.  I have heard of similar layups being used for boards but the specifics of the board and its likely use would need to be known to make a good judgement call.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Can any of the EasyComposite staff lend some advice?

So thicker layers would be stronger than multiple layers of a similar weight?

So how many layers would you recommend with something like Carbon/Kevlar?

Yes the carbon will damage more easily. But also easier to repair. 

A few more questions in addition to my first ones!

1. When using a foam core (e.g. in a kayak hull), should the foam run right to the edge of the laminate? And if it should, how do you seal the ends?

2. Thinking about the design, I would like to have either an orange or white gelcoat for the top half, but have transparent decals (such as writing) so it shows
the Carbon underneath. How would I go about achieving this?

3. After watching this video... https://www.youtube.com/watch?v=0N-LiWRA7RQ
I have also been intrigued by Innegra and wonder whether this could be used within the layup to achieve a better result? Could someone explain what effect it
would have pairing it with Carbon, Carbon/Kevlar, S-Glass & Diolen in terms of kayak strength and durability? Would it work either side of foam core with one of the other
composites on the outside?

What lay-up are you going for?

Won't carbon on the outside damage easier?