Not bad.
Would be neat to have a hall effect sensor monitor crank position, then feed that to a micro-controller. Fire the coils off with power transistors from the micro's output. Use a constant voltage and vary pulse width to control output power (and speed). You'd have to be mindful of the back emf of the coils, but that could be shunted with diode.
But, the brass switches are simple and give it a steampunky feel.
Like you, Terry, I would have made my crankcase differently. Probably from welded plate.