They have done quite a bit. Not only adding over 1000+ plays but they've also expanded the CPU playbooks. I guess previously, the CPU ran the same 35 plays a game. That's why you'd see screens on 3rd down all the time, now they've expanded the CPU to full playbook and they do use the full playbook which makes the game better.
Regarding defense, they have updated the CPU playcalling logic. Website says "Defense playcalling is set to match NCAA league averages. 32% Man, 26% Cover 3-4-6, 16% Blitz, 11% Cover 2, 1% Cover 0 Blitz.".
I don't think they've done anything to the fatigue but you can notice the other improvements. It breathes fresh air into this game and it definitely makes it more challenging.
To read all the changes, here is the patch notes on the CFB website:
https://github.com/cfbrevamped/CFBR-...otes/PC-PS3.md