One way to reduce rocker (this is how the Rogue River boats were
made) is to make a curved chine edge.
To do this to any of my designs, cut out and layout the
side panels as specified. Then rip a 3/4" x 3\4" x 16' strip of pine or fir from a carefully selected, straight
Lay that ripping flush to the chine edge. Clamp the ends
loosely to the ends of the panel, at the stem and
transom connection points. Bend the middle of the
ripping upward 2-4" at the middle, upward toward
the gunwale edge. Bend the ripping upward (toward
the gunwale edge) halfway between middle and ends too,
but bend it upward only half as much as the middle.
The ends are still flush to the chine. Fiddle with
the bent ripping until it makes a smoothly arching
curve, from ends to middle. Mark that edge with a pencil.
Remove the clamped ripping. At each temporary rib layout line
carefully measure the distance up from the chine edge to
the curved pencil line. Write these distances down. I do
it right onto the plywood. Now cut to that curved line.
Flop that panel onto the other side panel and trace out
a similar line, using the first panel as a pattern.