I considered the drum breaks myself for the look. I kinda like the way the drums look...old style like you said. I just didn't know how well they would hold up. Real good stopping power? How long before the shoes wear out? Can you replace the shoes or would you have to replace the whole wheel? All of those are the concerns I had for going with drums because of my lack of experience with them on bike wheels. Do you have any experience or thoughts on those items?
As for the jackshaft idea, that would probably work pretty well, and not a bad idea i must say. Having the engine centered better would be nice, but then there's more parts and more fabrication to be done. Probably just wait and see what stuff I end up having laying around when the time comes.