USC definitely has a good incoming class, but it's silly to think that Carroll wouldn't want to prove that he can win in the pros.
Silly for you. Quite a few sucessful college coaches have gone on to regret coaching in the NFL. You don't mess with job satisfaction and a good thing. Pete has said "In the NFL you get one 1st round draft pick each year at USC I get 7 or 8 each recruiting season." His last 5 recruting classes have been stellar. He maybe the new Bear Bryant or Rockne.
I wouldn't bet the farm on that. Nick Saban thought he was going to conquer the NFL after leaving LSU, only to cut bait and run back to college ball after two years. The fact he went to Alabama has every LSU fan pissed...
Pete Carroll has a great thing going at USC, and from all appearances, he's having fun. If I were him, I wouldn't even think about going back to the NFL.