re: Will the SEC fall apart without Saban?

I think you're asking the wrong question. Will the Big Ten+ fall apart with its nation-wide footprint, travel and fan difficulties, unnatural rivalries and other complications?

The footprint of the SEC is still contiguous and all of the schools have some history. The SEC has had many dynasties over the years. Obviously, Bryant and Saban. But Tenn. had General Neyland; Ole Miss had Johnny Vaught; Florida had Steve Spurrier; Arkansas had Frank Broyles; Texas had Darrell Royal (even though that wasn't as SEC); Auburn had Shug Jordan; not trying to leave anyone out, but the SEC will continue to be the toughest and most successful league in all the sports that aren't frozen.