re: What happens after Daniels leaves?

The reality is that while having a great QB can lead a team to great things, relying on that alone leaves you vulnerable when that QB leaves.

When you base your team on defense and line play, you don't have the same ups and downs. While it's harder to get a national championship caliber team when you have solid QB play and great defense and lines (like UGA has done the past couple of seasons and Bama has done most of Saban's tenure), when you do you can handle slight misses at QB (not a total dud, but a less than stellar performer).

A great QB playing for another talented team can still beat you (like Trevor Lawrence and Deshaun Watson for Clemson or Joe Burrow for LSU winning titles), but you'll still be right there.

But it's not easy to recruit the other positions to the point that QB isn't as vital. Most teams need that stud at QB, which is why strings like Bama has had are rare.