Hey ProfScot,
Thanks for the feedback. Whatever agency distributes mass transit money from the state [[I think all local transit systems in Michigan get some money from the state) should operate the card system. I guess that's not MDOT. Do they just do roads? The details would need to be worked out, but I don't think they'd be the most contentious details ever. At the end of the day [[or end of the year, as the case may be) I would suspect each system would have more money than it otherwise would.

As for the equipment, I can't imagine it would cost mega millions. It's not like Michigan has tens of thousands of transit buses and train cars. I imagine also phasing it in over a couple of years. The card vending machines would also offer mucho advertising opportunities all over the place, not that I suspect that ads could fund most of the system...

Not having interchangeability benefits no one. SImilar to railroads in the 19th century having different gauge tracks. Railroads made more money when they standardized equipment.