Way back when a Big Ten expansion was first on the horizon somebody on this board pitched the idea of adding the University of Toronto. We all had a chuckle, but the guy was serious. And frankly, he made a bunch of good points. Sure, their sports teams - such as they are - are totally inferior, at least for now. But, you'd add an AAU university (and the top research university in Canada), and you'd get a huge population base (Ontario is about 15 million--more than any BT state, and perhaps a good chunk of Canada).
In terms of expansion, a lot of options in the US would just be cutting the same pie into smaller pieces. U of T would introduce a much bigger pie.
It would take some time, but I bet they could eventually be competitive.
I know, a crazy idea. But it would be a game changer.