1) Barry was great--as someone said earlier, one of the best coaching hires of the last 50 years for any program. He revolutionized the program, and continued his success as the AD. But his time has passed. He retired what, a decade ago? It's someone else's turn, and the concept that he is the only person who can do this is silly. No reason to tarnish his stellar reputation by bringing him back (if he were interested), and no reason to step in some other capable person's way. Also, while he did an amazing job building the program, this is about hiring coaches. His approach to that was (1) hire his own assistant; (2) hire another up-and-comer who didn't work out; then (3) hire another former assistant (who did work out, but word on the street was that he was fading fast at the end). So it's not like Barry had some magic sauce as the AD to find the right coaches.
2) I don't pretend to know who the right next hire is, but I'm not opposed to someone like Polaseck. Eck might also be a good choice, and there are likely several others. What I would like to see is someone who has had success building a program, has had success in the last three years, and has teams with an obvious identity, preferably one that includes strength on both lines. [edit] I should note that Barry didn't fit any of those, except possibly the last; he was an up-and-coming defensive coordinator who had earned a shot at his own program--and he was a home run hire. But he was brought into a garbage program; Fickell--and his replacement--are brought into a good program that has fallen on hard times. Not the same situation. [/edit]
3) Leonhard would have been a good choice three years ago, but--like Fickell, who was also good choice--that doesn't mean he would have worked out. That's something everyone needs to keep in mind about these things, the hiring process is different than performance. Fickell was a good hire at the time, but it turns out he wasn't the right coach for Wisconsin. At least that's the way it sure looks now (if I were in charge, I would have fired him by now--unless there's some magic hid behind some curtain that we're not privy to). The next time will be a similar calculation: whether he is a good hire at that moment is different than whether he works out. Hopefully we can learn things by past mistakes, but there's no guarantee in any of these hires, especially in the current, rapidly changing environment of college sports.
Would Leonhard be a good hire now? Maybe. If he understood that recruiting wasn't his strength and hired underlings who could make up for that deficiency, he might be really good at culture building, which is something that Fickell has apparently failed at. This program desperately needs an identity. And Leonhard was coaching great defenses without 5-star players. The fact that he's being groomed to be a head coach in the NFL tells me that he has the coaching chops. The question is whether he has the college coaching chops, and that means understanding recruiting. But I'm not a Leonhard or bust guy. I think that based on how the search went three years ago, he might not take McIntosh's call--but he would probably take a call from someone who replaces McIntosh.