Here's an idea about what the SEC could do with regards to expansion, since it's apparently a thing now. The SEC should add to what it has by picking up WVU, Louisville, Kansas, Kansas State, and Missouri, for a total of 18 teams.
So, the football divisions would be the nine schools in Alabama, Mississippi, Florida, Tennessee, Louisiana, and Georgia in one division, Kentucky and all the new pick-ups since 1992 (the five listed above plus South Carolina, Arkansas, Texas A&M) in the other. This means a lot of travel for the new schools, but football and basketball can afford it. The division made up of the older SEC teams would be the football division, the new one a basketball division.
The conference would play nine conference games in football: round-robin schedule against the other eight teams in your division, plus a team in the other division. I would give schools freedom to schedule the inter-division game: Tennessee and Kentucky want to play every year? Sure! Florida wants to rotate three teams? Whatever.
In basketball, I'd subdivide the divisions. Play a home-and-home with your four biggest rivals in the division every year, one game against each team in the rest of the division, and a rotation of six games against teams in the opposite division (for a total 18 conference games). This would have everyone play their biggest rivals twice a season, their other division rivals once a year, and get regular games against the rest of the conference.
All other sports would ignore the divisions, perhaps playing in pods or protected rivalries with rotating games. This would cut down on travel costs and let rivalries in individual sports to flourish.
Such an expansion would protect all the important football rivalries. It would put the SEC on TV sets stretching from Texas and Kansas in the west to Pennsylvania and Florida in the east. It would create unquestionably the strongest athletic conference in the country; for basketball and especially football, you'd have divisions as strong as any other conference.
It would also protect and nourish the weaker halves of the two money sports. Missouri, for example, can build and improve their football program without having to play Florida or LSU every year. Basketball is slightly more evenly divided, but it would help (say) Mississippi State's basketball team to not have to necessarily play Kansas, Kentucky, and Louisville all in one year.
There are some big downsides. The new additions probably won't add as much money, even with the new TV contracts, as they'll take.
More importantly, it will change the football product. The SEC probably will never have another undefeated season. No matter how good (for example) Auburn ever is, they will not win every game against the average LSU, Florida, Georgia, Tennessee, and Alabama team in one season.
The football title game would also be much less important and impressive. You'd have a three or four loss Georgia or Florida beating the pants off a one or two loss Texas A&M or West Virginia every year.