Do you mean South Carolina? Because I wouldn't say in a hurry, Clemson and South Carolina have been neck and neck for a while with South Carolina only gaining ground in the past few years.
If you mean Texas A&M, they are not #1 in the state yet, but I was a huge supporter of adding them. Really big, going back to over a year before they were added. It's about what they had to offer and A&M had a lot to offer. Virginia Tech ain't no A&M, and neither is NC State. That's all there is to it. Heck, I'm not sure either are Missouri...
I don't think people get how horrible Virginia Tech's athletic department is. They have like one national championship in anything, ever (I'm trying to remember if they actually won one at all), they earn much, much less than Virginia, and they won something like one whole bowl game prior to Beamer. I'm thinking I might be giving them too much credit, but to be clear here we're talking about something like the 60th all time football program, and that's what they are good at. Mississippi State hasn't exactly become a juggernaut in the SEC, nor has Vanderbilt...
I don't dislike NC State nearly as much as I dislike VT, but NC State is just so far behind UNC. They are a clear consolation prize, and North Carolina is no Texas. Their brand is a national brand, that has ties to the likes of Michael Jordan. They're more like Notre Dame, in that people will fawn over everything they do (in basketball). NC State, and not even Texas A&M are going to get that level of adoration.
But... I'm not saying VT and NC State are horrid additions. They have to be in a list of candidates, I'd just hate to see the SEC get consolation prizes from both states.