Living in Minnesota, I've had the opportunity to watch Jerry Kill steadily build the Minnesota football program. I think the main difference between him and Paul is the presence of a steady basic plan. He doesn't try to do anything other than what he and his staff are good at offensively and defensively. They don't switch defenses from year to year, and they run the same basic offensive scheme they came in here with - the same one they have used in 4 programs of varying size before they came here. They recruit players that fit the system rather than trying to fit the system to the few good players you have.
Most of Kill's assistants have been with him for over 10 years and I would be willing to bet that even if one of his coordinators were to leave he would find another coordinator who would run the HEAD coach's system. He's not going to hire someone who will teach an entirely new offense to the players. The players have been recruited for that particular brand of football. I never really get the idea that Coach Rhoads has any solid beliefs in how offense should be played. As a result, the Cyclones wind up with new assistants teaching THEIR way, changing techniques and terminology annually. Players are recruited for an offense that is never run once they arrive on campus. Offensive linemen are asked to play differently every year, with new terms, and new expectations. To build a program at a lower level football school like Minnesota or Iowa State you have to be enough of a leader to have a plan, and then to stick to it. Your assistants need to do what YOU, as the Head Coach want them to do, not what THEY want to do. You need to recruit the players that fit that system. And you are NOT going to get 4 or 5 star players unless they grow up in your back yard, so you have to be great developers of talent. You have to be great at finding players who have not peaked in high school. You have to know yourself and your system well enough to know which players you can turn into solid players who will thrive in your environment. Then, you have to develop them over 4 or 5 years.
That is what I see happening at the University of Minnesota. I really like Paul Rhoads, but by comparison his leadership looks responsive, not planned. He swings from one thing to another trying to find something that works. It's a stark difference.