If some BE schools do defect, then what's left of the BE, if anything, won't be worth moving into. They could still be an amazing basketball conference, and Louisville could help fill the void left by Syracuse's departure, but in football they'd be worse than C-USA. So why should Louisville even move?
Agreed, that a gutted BigEast might not be a step up from C-USA for Louisville. TCU, SoMiss, ECU, Cincinnati are all good FB teams - while a BigEast without Miami, Syracuse and BC (for instance) would be a one-trick pony of Va-Tech and 4 mediocre to good schools (worst to best: UConn, Rutgers, WestVirginia, Pitt). If Va-Tech goes ACC instead of either Syracuse or BC - then the BigEast is even worse off.
Basketball would be better than C-USA though - with the 6 non-FB members (St. John's, NotreDame, SetonHall, Georgetown, Villanova, Providence) and then maybe either BC or Syracuse (if both don't end up leaving for the ACC), UConn, and Pitt, and now adding Louisville - especially if the move involves Cincinnati too. That would be a heck of a BB conference!
One interesting possibility is a new conference with Cincinnati, Louisville, some old BE teams like UConn, G-Town, and Villanova, and the best of the Atlantic 10 like Temple, Xavier, etc. They could form a phenomenal basketball conference a notch above C-USA. Not sure what that would mean for football. Might not be worth having a conference at that point.
One - this conference would kill UL and UC FB - and UConn FB couldn't afford a move to a non-FB conference either (you've only listed 4 FB schools (2 really weak ones) - so I'm assuming there are no others in your new conference).
Two - two teams in Cincinnati (Cincinnati and Xavier) and two teams in Philadelphia (Villanova and Temple) in the same conference might be a little redundant. Of course, they are all fine BB schools, but conferences and TV contracts like multiple markets. When 4 of your big 7 cover only two cities, you need to re-shuffle a bit.
Pitt can make a decent push for being the 12th member of the Big 10 I think if the BE disintegrates.
The Big11 doesn't want Pitt - or Syracuse or any other eastern school (both have been rumored and flatly denied in the past by the Big11). There was even a rumor about Rutgers (can you believe it?). The Big11 seem completely content staying at 11 until NotreDame finally picks a conference (theirs or someone else's).
If NotreDame picks a conference that isn't the Big11 - expect to see the Big11 look west to balance the divisions in FB power. As it stands the 3 major FB powers would all be in the east division (PennSt, UMich and OhioState). The Big11 needs a traditional FB power in the western division to balance the potential Big11 Championship ticket.
Does anyone think a UMich-NW'tern, OhioState-Minnesota or PennSt-Indiana match-up has enough drawing power to bother expanding the conference to get? Illinois, Iowa or Wisconsin would be the only western schools the networks would want to see in that kind of game - and it still wouldn't be a must-see. The networks would want a chance each year at a premiere match-up like NotreDame-UMich/OhioState/PennSt.
Someone commented on here that UMich and Indiana don't want NotreDame in conference - well, UMich didn't want PennSt in either. And the lack of support from Indiana and UMich didn't keep the Big11 from inviting them just a few years ago. Fortunately for the rest of the Big11, UMich doesn't pull the strings for the conference.