There's literally no way that it could happen from a B1G network perspective, but from a CIC perspective, taking on UNC, UVa and UT would be a major academic coup for the B1G... anways, nothing to see here, carry on...
I still think Vandy could be a wild card. Again just throwing it out there because I am bored.
Assuming ND joins (eventually) they can help take care of the NE and the catholic population.
Looking to the west, the only real options are Oklahoma, Okie State, Mizzou, Kansas, Kansas State, and Iowa State and none of them would truly expand the footprint. Oklahoma has the best chance but it won't happen.
Looking to the South (SEC territory) there are a few options in play. I like the idea of adding an academic institution like Vandy. Also keep in mind how much that would hurt the SEC in terms of losing their #1 academic institution (by a long shot). Vandy does not have a huge athletic presence but the B1G brand is large enough that there will be fans, alumni, etc. currently living in TN, KY, etc to add $ to the pot.
The Carolinas are growing at an exponential rate. Adding a presence down there would also help to expand the brand.
Finally, I have been pushing GT and the Atlanta idea for a while now for the same reason.
Plain and simple Delaney is smart enough to have a plan. It isn't just what adding a school can bring in location, alumni following, research $, TV Viewership, etc. It is a combination of all of those. There are approximately 4.5 million living alumni from the 12 schools. Combine those with the people who just cheer for one of the B1G teams and we are talking about a huge number.