Dave Gentry's 12' kayak is a little simpler. I don't have access right now and don't know the specific model. gentrycustomboats.com
He uses staples to attach the skin which might be easy, although sewing the SeeBee skin is relatively simple.
What were you thinking for the skin?
The polyester skin typically used for SOF or Yost's fabric reinforced PVC might be difficult to get.
However, I read of one person using old plastic/ fabric signs for a skin. might be difficult to get wrinkles out. I believe Gentry's geometry would be easier with such material.
I have not built any of Dave's boats - just looked at them for a long time. They are typically wider which would be more stable for people not use to boats.

One problem with typical lumber is joining the pieces to get the 13' or greater length. You've seen Yost's bolted splice blocks I'm sure. With material other than Cedar the frame will be a little heavier, but it probably won't matter as a start. Sealing the edges of the plywood frames will also be a concern. Paint would at least last for a little while.

Contact Dave thru his website, he has been helpful to me information requests.

Good luck, sounds like a great idea.