George G asked me about Bjorn Thomassen's Frej design in the 'Basswood' thread.
I've built two Frej kayaks - one 16' and another longer 18' version for possible use on trips.
I like them both - they are quick, roll very easily and handle waves and wind well.
In breaking waves from the side, the low back deck means that there will be 'green' water over the deck and the kayak gets knocked to the side. My Mariner boats are much better in this regard, riding over seas.
Frej has quite a lot of rocker and the paddler position means that a bit of skeg is needed for most normal paddling.
Both of my Frej kayaks have home-built skegs; I copied Reg Lake's excellent skeg design with the actuating cable entering the side (not top) of the skeg box.
On the 16' Frej, I installed the skeg just aft of the cockpit bulkhead- a 'skeel' like many of the Sterling boats have. I did the same on the 18' Frej and it wasn't effective in preventing weathercocking in stronger beam winds. So I moved that skeg aft to a more 'standard' location, behind the rear hatch. My advice on the skeg for any Frej would be to put it aft in the area shown on the plans.
Right now, I'm building a Njord (very similar design to Frej) and it will get a Kajak Sport line control (System 4) skeg, aft.
About foot room....
I've come to much prefer bulkhead footrests vs adjustable footpegs at the sides. That's the main reason I paddle my 18' Frej on day paddles. Having a little bit of 'extra' space lets me move my feet around a bit; most of the time I paddle with my knees in the middle of the cockpit and my feet a bit 'vertical'.
I wear Sz 10 shoes. As designed, Frej has good foot room for my feet if the length of the paddling shoe is 275 mm. I have several pairs of paddling shoes that are 290 mm and they are a tight (impractical) fit in Frej.
On my Njord build, the front deck will be higher !