I think it is reasonably clear that anyone advocating privatizing mail is going to have to address the issue of the cost of delivery, either by some kind of sub

I think it is reasonably clear that anyone advocating privatizing mail is going to have to address the issue of the cost of delivery, either by some kind of subsidization by the government (not necessarily federal.. for example it could be done at the county level to promote people living there) or allowing companies to charge appropriately.