Assuming these images get to you,via the Forum's "upload a file" function.
My Petrel "Purple Heart" launched without fanfair can be seen in a tidal puddle.The stick has done a couple thousand kms,the boat just a couple in her sea trial trim.Her weight is just a single hand's worth onto my shoulder, after a couple km paddle anyway.Less than 2o Kg I am guessing.
Deck in 4 mm thick x 12 mm wide Alaskan yellow or what ever you all it.The fake chalking is WRC last but not least is the three modest strips of Puple heart ,hopefullY c.i.t.e.s OK.that the boat eventually got her name from.The hull is dark WRC sides and light colored sap wood WRC down the bottom

The skeg is an amalgamation of you're ideas,but with my influence...The double skeg idea I had was abandoned hearing the 1950's boys results of experiments to thier surfboard fins, twins making for a wilder ride .My single and central slot runs through the deck and hull.It works entirely underdeck with a loop of cord up haul and down haul .I operate it with both feet, toes on plastic toggle balls.The loop goes through the front bualkhead as well.I discovered serendipidously ,that I had to pull one and push the other ,to unlock the loop from the friction.The skeg changes the boat more than enough to be worth the work as I have later discovered in proper waves and ,ahem, with proper decklines.
. A second pic at a much smaller size setting is all part of a "ludite's learning curve" but showing a little foible I keep repeating with lhe last three boats at least [underdeck and in a secret place of course.]
cheers, from Paul.