Well, I resized the trike (made it narrower, increased the caster, tightened turning radius, raised front end) with all the associated messing around. The thing no longer scrapes going up and down inclines. I also refined some components, like the freewheel on the motor. It had a tendency to work itself loose. I welded some stuff and used loctite; so far, so good. I no longer have any complaints about the steering, it is far less twitchy and more self-centering. I took a lot of the play out with nylon bushings.
I added brackets to the front spindles to create attachment points for the front brakes.
I had a devil of a time figuring out how to balance the 2 front brakes with a single pull-handle. I finally settled on runnng a single cable, caliper to caliper, and running a cable from the handle to it such that it pulls on the single cable and actuates both brakes. I do not know for certain that this will work yet, since I need to lengthen the caliper arms before I can mount pads. I am thinking that it should balance nicely though, since any resistance on one side will automatically create more pull on the slack side. Hopefully it will be close enough.
Here's a picture of the spindles. They are ugly as sin but strong. Once this thing has been rolling around awhile, I will probably remake them in a more elegant, better looking, and lighter-weight format. Note how the cable runs straight into the frame.
Once I have the brakes tweaked and the shifter working, I will install the front floorboard, add reinforcement to the frame, and ride it for a few days. Then it's time to add POWER!