Rolf,

too many variables, to little time to give you a back of the envelope estimate. Design path goes something like this:

1. Determine maximum righting moment.
2. Determine worst case lift distribution from rig.
3. Using above info calculate max side force on foil
4. Calculate lift distribution on foil.
5. Calculate moments and forces on foil.
6. Determine young's modulus and allowable stresses on selected timber.
7. Determine young's modulus and allowable stresses on proposed laminate.
8. decide on allowable flex on fully loaded foil.
9. determine section modulus of proposed foil.
10. adjust number of carbon layers until deflection goal is achieved.
11. confirm maximum stress due to bending in various components.
12. adjust laminate to suit.
13. check shear strength of core (particularly in way of hull exit).
14. Repeat all of the above because I've almost certainly lost a decimal place somewhere.

The exterior laminate makes it more durable but also must take into account hoop stength and twisting, yes you can use glass but it will be heavier.

Profile (meaning the shape of the board when view from the side) is in theory very important, however there is a trade off between efficiency with the foil down and up. If you taper the lower end you can reduce drag, however, it is at the expense of drag when you pull the foils up as you end up with slop in the case or a small amount of foil left down.

Section shape is important but don't dwell on it too much the shapes people use (with the exception of Richard Roake, Martin Fischer and their peers), be they NACA or any other profile are merely part of systematic analysis programs where one variable has been changed at a time, they are not "ideal solutions", so pick one which has the characteristics you want and do your best to match it but your priority should be a fair (consistand curvature without waves) shape.