re: Who will be the next elite team in the SEC?

There isn't a caste system but certainly there are those who have more and those who have less. The SEC shares better than pretty much anyone resource wise but still the fundamentals will always strongly favor certain schools. It's money, facilities, recruiting base, and fan support that determine quite a bit. A school can overcome it to an extent and overachieve but consistently beating schools with far stronger resources is really tough and it is getting tougher. That said Bama and LSU actually aren't the strongest resource wise in the conference though simply because of the size of their states but they are very strong, they have been absolutely hitting on all cylinders though and for now are certainly above those who "have more".

That said, the schools that have elite resources are these:

Florida
Georgia
Bama
LSU

A&M could be counted or not on this list because they lack a few things. The potential at A&M is strong enough they are the only school that could really go toe to toe with Florida long term.

Auburn is next and I'm amazed at the size and passion of their fan base and finances considering Bama is still the bigger name and it is not a very big state. They just do it on sheer will. They seem to be hitting a down cycle though and could get knocked down for a few years if they aren't careful.

Tennessee has it all but the recruiting base. I have never understood why that state doesn't produce better talent. Still everything else if off the charts there so they can buy a lot.

Arkansas has a lot in common with Tennessee, though the money they have is from a smaller pool of people. Just aren't many great football players produced out of the state though.

South Carolina and Missouri have a lot in common. Though SC has better facilities and more talent per square mile Mizzou has a greater population base to pull from and more potential, they just have never truly been dedicated to great football. We will have to see how much the SEC momentum carries them.

The Mississippi schools have a decent recruiting base and some passionate fans but simply don't have the money or facilities to keep up. They can overachieve from time to time but long term they are never going to be able to keep up in the SEC West. Almost every conference opponent they play has twice their AD spend.

Kentucky could actually be a decent program if they cared about something other than basketball. If they invested in their program they could own the state recruiting wise and make inroads into some Big 1G territory. They seem happy though to get big checks from the SEC though football wise and put everything in basketball.

Vandy is of course stuck at the bottom long term for reasons everyone knows.