I got my boards back from OSHPark. The basic servo control functions perfectly. As I said before, I've got an MMBT4401 acting as a common collector to turn the servo power on and off and the control pin comes straight from a PWM pin. It works just fine. I attach a Servo object to the pin, set the angle, then power the servo on for "enough" time, then turn the power off and detach the Servo object.
I have power control over the rest of the circuit with another pin. I do have to turn the rest of the electronics (display and GPS) off before attempting to run the servo, and I also need to reduce the brownout detection to minimum, but that done, it works.