Looks good. Remember not to add too much as it makes a bigger difference than most people would think. Yours looks about right if you're building a guillemot. That is a guillemot isn't it?

My kayak turned easier than a guillemot (every paddle stroke would make it turn and it took total concentration to keep it going straight). While I added about 2" at the most extreme location, it was never lower than the bottom of the kayak (I wanted to be able to sit in the kayak on the grass and not be sitting on the fin). The fin made it track a lot better.