Thanks all for the further suggestions and witty repartee. Some updates:
1. This morning was ride 6 for about a total of 180 miles. I went back and did the skipped exercises and have been riding on the obstacle course that is Chicago's Lakefront Path, and on the north shore. I have relaxed into the recline and feel pretty comfortable with the MBB / FWD at this point, pretty stable most of the time. So I am nearly over that hump.
2. Re the headrest -- I am making progress. Not perfection, but much better. I ordered the CB Performance Adjustable Headrest but it has no installation instructions (per Robert H.) and (this is embarrassing) not intuitively obvious to me how it fits. But I used the second sock/pad that comes with it, bought a kid's arm floatie, cut it into a strip on the seal (so the air stays in two separate compartments) and sandwiched the floatie between the two socks with the padding. It's held together by three small bungee cords, and I can inflate the upper and lower chamber to different pressures. It is working pretty well but I am still tinkering. Will add a photo when I can.
3. I posted this in the Race/Event forum, but I am going to ride in the Race The Lake Century on Sunday in Fond du Lac, WI? This is a hybrid race / supported ride through some very pretty country with some elevation change but mostly pretty flat. I rode in it a few years ago on my Bachetta CA 2.0, and I confirmed with the organizers this year that it is recumbent-friendly (don't know what they'd do if anyone on a recumbent actually came in the money). If you're going, too, let me know.
d