Nebraska is not a desirable location for any established coach. If they understand that, at least they can begin to narrow their focus. Their options will be young up and coming coaches from non-power 5 schools, coordinators, or someone looking for redemption, like O'Brien. All of their recent hires have been disasters. Pelini is a Neanderthal, Riley was a fish out of water and Frost is in over his head.
Someone mentioned Fleck, why would he leave Minny? It is a better program than Nebraska. Some NU fans have mentioned Matt Campbell, but why would he leave ISU for Neb/ he has a better job now. Matt Rhule... if he is out of work after this season, given his reputation as a college coach, why would he take that job? Surely better jobs will become available if he sits out for a year.
Nebraska needs to understand who they are and find a coach who fits. For example, ISU poached Campbell from the MAC; Baylor poached Rhule from Temple; Cincy got Fickell, who was a top flight coordinator. Those should be the model for Nebraska IMHO.