What I am looking at now, is the
Pfiff Capo.
I think this could be a more road worthy machine. With the paired wheels in front it would be easier to avoid running one of them over a bump. And the 7-speed version has front suspension and a suspension seat post. The front suspension appears to have a bit of articulation to it, too, which should help reduce the trike tippiness. And the overall larger form factor means it has normal length cranks and the seat could be raised to a proper height. I'd like to fit it with a pedal assist electric system, the kind with torque sensors. Dial it up high, because I am weak, but still require light pedaling. Because that would be super good for me, and fun too!
In my searching I found a shop that sells them, which is less than an hour away. I'm hoping they have one on the floor, that I can go see. I have written to them and will see what they say.