As much as our friend Billy from FSU will protest, adding Clemson and FSU does nothing for the SEC in terms of a revenue bump.
UNC & UVA are the jewels in the ACC when it comes to adding revenues to a conference.
There are only a small handful of schools that can increase revenue for either the SEC or B1G. Notre Dame is the obvious one but as
@UConnJim said, if they get a bump from NBC (which is likely, especially if as has been reported, that NBC is looking to create a B1G/ND doubleheader package) they will stay where they are and continue to take advantage of the ACC like they did to the Big East for years.
After Notre Dame, UNC & UVA the pickings get very slim in terms of schools who can increase revenues for a conference. Regardless of what some people think, Kansas is not a bell cow for the B1G and no other B12 schools are either. At that point the only schools left are a couple PAC schools (USC & UCLA) but, that brings a whole bunch of logistics issues to deal with so I'm not sure it makes sense. Maybe an extra $30-40MM may help it work but flying Olympic sports teams all over the country is certainly not ideal for "student-athletes".