Bob,
The main reason I built the horizontal stabilizer like that, was to distribute the strength of the stressed skin across the span of the tip to balance the load forces of the elevators back into the fuselage from the tips. Those wingtips of the horizontal stabilizer are only 1/8 of an inch thick so no way to embed t nuts in there. The structure I built was to be able to lose the external tail braces while adding airfoil structure to the tail feathers. I have the glue drying on one part of the skin that was applied to the stab tonight and am headed back to the workbench after this came out to get a cup of coffee.

edit to add:
I had hoped to be a lot further than this but i had about four versions of the tail group drawn up before committed to build this version. Rather than use counterbalances and increased span to increase the elevator area i have decided to go with a longer root cord, which should increase control response, because of the increased area and the fact that this will move moment arm back just a bit also. While keeping the major portion of the span of stab and elevator closer in to the roll axis.