There isn't a good defense in the SEC aside from Florida. Bama's defense isn't what it once was, and their offense isn't as good as it should be either. Right now, it looks like Oregon is the best team in CFB.
As far as Nebraska, our recruiting has improved greatly and is no longer an issue. The thing that needs to be fixed is the defensive scheme. Giving up 6-7 yards every time the other team runs the ball is demoralizing. If you're another team playing Nebraska, why would you ever throw it until you absolutely had to?