Part of the SEC "culture" is the long standing rivalries: Iron Bowl, 3rd Saturday in October, among others.
My proposal: move both Alabama schools to the East, move Vandy to the West.
Putting Bama & Auburn in the East preserves the 2 "sacred" rivalries (Iron Bowl & 3rd Sat. in Oct.)., keeps UT/UK, keeps AU/UGA, and with UT & Vandy as cross-division rivals keeps that rivalry.
So, we'd end up with this (paired as rivals; current & untouched are in italics)
Ole Miss UGA
The bottom 3 can be negotiated and changed. One could argue that LSU/UF could be changed, too.
MSU's current "permanent" rival is Kentucky, but they don't act like it. I don't think fans at either school would be opposed to changing it (as an MSU alum as well, I know I wouldn't, especially if Bama's the permanent rival since Tuscaloosa's 90ish miles from Starkville).
If, however, this is preserved, put aTm & Bama together (something about Bear Bryant coaching both schools makes this a potential rivalry) and Mizzou with Auburn (two Tigers together). If the SEC would rather preserve LSU/AU, then make it MU/UF which would be hot games for Mizzou in September in Gainesville, and cold games for the Gators in Columbia in November, both of which would/could be marketable.
Ole Miss' current permanent rival is Vandy, Bama's with UT, and Auburn's with UGA: all of these would now be divisional games.