Jeff, sounds like tpyical CA weights and loading - appear overweight but fly beautiful, but not floaters like Dick Hanson's planes. Mine is 8lb 4oz without motor, batteries and elevator/rudder servos.
Looking at the stab, I can see how to increase down throws. One of the guys here experimented with a spare 2.6 wing just to see what he could accomplish. He cut back the trailing edge of the lower wing surface so there was no interference with down travel - ended up with more throw than you could access with normal CA control horns. The gap is easily sealed with mylar gap seal the sail planes use. You would also need to cut a notch for the elevator control horn.