G'day Merijn,

Cool looking boat. However, as mentioned the sheerline at the cockpit is a bit close to the waterline. This may not be a problem with a skirt on though. i paddle a surfski (red7 surf70) and the overall heights at the rear of the cockpit are 210cm from bottom to sheerline and 240cm from bottom to top of deck. Of course skirts aren't used with surfskis so the sheer does have to be higher than a kayak.
Regarding the construction method, have you considered a hybrid? fast hull construction with a chance to get creative on the deck.
Whichever way you go, I look forward to seeing the end result.
Cheers