Have you ever tried a more level seat angle? Forward sloping like you have generally puts more weight on the hands.
is it possible you have such a slanted seat because the seat to bar distance is a bit too far (and why you like the reverse trekking bars?)
After I repositioned the saddle, I rode the bike on a 30-mile road ride in southern Wisconsin. It was quite comfortable, so I thank you again for pointing out the tilt. While I was on the ride, I was trying to figure out if the decreased tilt was changing the pressure on my hands, but really couldn't detect any change from before. I found myself wondering if the reason I like the controls so far out in front is that the frame is too small, or the stem too short. At any rate, the bike is comfortable in its present configuration.
The road bike (Airborne "Carpe Diem") trekking-bar conversion continues. The XTR shifter for the rear derailer works perfectly (whew!). I'm waiting for the arrival of an inexpensive set of friction shifters to experiment on the front. Once I see what works, I may replace the shifter with a nicer one. We'll see.