Ok I try to not forget the ruler and take some pictures of the stock Bimare foils of my boat.

For the section design, I used indeed x-foil, but not in the inverse mode (I never managed to use it for symetric sections). I started from NACA for digit foils, modified the gemoetry based on my knowledge to achieve high maximum lift, higher cavitation speeds and less drag at a given lift ratio. I tried to avoid making "laminar-sensitive" sections as well. So I got some hundreds of new sections geometries, which I run through X-foil and put the customer for the difficult question which exact combination from lift, drag and cavitation he wanted. Basic outcome was, that you can have much thicker foils with more maximum lift and less cavitation for more or less the same drag as a conventional NACA 0012.
In my opinion those foils are better than most available sections, which are too thin or try to be laminar.

My friend used a similar construction method for his Tornado rudders as you. But after some sailing the rudder crushed the foam core at high speed, partly beacuse bad glueing (he didn't have vacuum equipment), but mainly because of to thin CFRP skins. Taking wood resolves the probem of core crushing and you still can stay with the thin CFRP skin (or glass as on the T's). I guess machining wood is more expensive though.

Rudder data are at home now, but maybe I will have some time and put them in a document, which I can share here.

Cheers,

Klaus