The difficulty of setting a national post rate too high—and I got this from Mr. Chopra himself on the phone once—is that private couriers would undercut that rate on high-volume routes, like Toronto to Montreal. I asked if he thought that some sort of regulation needed to be introduced to stabilize the market and make this functional, then, and he ran as far as he could in the other direction.
Basically, it just needs to be something that's predictable and makes sense. There are various ways you could tweak it. In Australia, I think they actually licensed their bags, and they call them eBay bags. Presumably, they got some funding for it out of eBay.