Building a successful football program is a huge mountain to scale. It's almost like this example: you can build a program quickly, ethically, and cost effectively....pick two.
It goes so much more deep than just hiring a good coach and having a committed athletic department. With a program like Kansas that has such a history of losing, you simply aren't going to get top recruits to take a risk coming here when we're competing with programs that are historically better than us (i.e. pretty much every other power 5 conference school).
The last time we had a winning team, we did it at the expense of having a somewhat insane coach (Mangino). While it was great winning a bowl game, I'm not sure he did it in a way that made me very proud of the program.
I think it could take a decade to get to a point were we'd have a solid, stable and winning program that wasn't propped up by juco transfers, questionable ethics, or some other issues. Win 1 game next year, 2 the next....in 3 or 4 years you're a .500 team with a cupcake-heavy non-conference schedule...3 or 4 years from that you're a .500 team with a legitimate schedule, and only THEN do you see a chance of prolonged success built on organic growth.
A great coach, fan support, and great facilities still aren't enough to get top recruits if they're looking at winning 1 or 2 games a year. I honestly think basketball is easier because you can be "pretty good" with 1 or 2 top players and a handful of "solid" guys.