Update on my modifications:

The original intent was to convert the bike to use drop bars and integrated shifter brake levers. It's just about all done now, and I'm very happy with the results. I wound up using Tektro Oryx cantilever brakes front and rear, and a mid-cage XT derailleur. I believe the Oryx is the narrowest low-profile canti's you can get. They are essentially the same as the older style Shorty 4/6.

I was afraid the brakes would get clipped by my shoes, but I'm glad to say that has never happened in the 20 miles I've put on them so far. The only "gottcha" that I encountered is the length of the included straddle cables. These brakes come with a "Z wire" style straddle cable, which are too short when installed over fenders. These cables are literally resting on my fenders in the retracted position. I imagine that these are fine if you don't use fenders. These will be replaced by a center yoke and traditional straddle cable when they arrive.

BTW, that's a one wheel B.O.B trailer attached. A common complaint about one wheeled trailers is that they seem unstable with heavy loads. Using that trailer on a small wheeled bike has an unforeseen bonus. The lowered center of gravity of the trailer itself puts less force on the bike and feels more stable than when attached to a large wheeled bike. Go mini bikes!