The best tips:
#1 Stop contemplating, and start building. It seems there are plenty of folks that suffer analysis paralysis. You have to start cutting wood and slathering epoxy, the boat won't build itself.
#2 Don't try and out smart Renn. Any "improvement" you come up with will take longer, cost more and the final product will be heavier. His design and techniques were developed over building 100+ stitch and glue boats.
#3 Tolman skiffs have been built by expert craftsman, rank amateurs and everyone in between to varying degrees of finish. They all seem to float, get you where you are going and back with relative comfort and safety and have landed lots of nice fish. So don't worry and refer back to #1.