I think it's odd that Rhoads and Walden's winning percentage was almost the same, when Walden came into an absolute disaster in all aspects, had Class 2A Iowa HS facilities and a downright obstructionist President. Rhoads didn't come into a great situation, but the facilities were being improved, and he had a supportive President and AD committed to building winning football. Not to mention, there was decent talent brought in by the Chiz, which might be a big reason Rhoads peaked in his first year. Yet somehow Walden is almost universally panned as a terrible coach while we have people arguing that Rhoads is a good coach.
I loved Rhoads enthusiasm and passion, but ultimately that works in short bursts only, and it has a shelf-life. As others mentioned, the realignment was a huge challenge he had to face, but ultimately he didn't succeed. As far as recruiting, some of Rhoads problem was conceding that he wasn't going to anything but diamonds in the rough. However, I think the hard truth in recruiting is that, especially, in the latter years, his staff flat got outworked by damn near everybody. I'm not saying they were lazy by any means, but the top three guys - Rhoads, Wally and Mangino were not exactly road dogs, and left a bulk of the recruiting to the lower level staff. I think when you combine that with their inability to connect with kids as well as say, the current staff, they were going to struggle. Also, for whatever reason QB development was very poor. Jantz, Barnett, Richardson all looked like they had tons of promise when they first came on the scene and you can argue they all regressed over their careers.
Mac clearly did some great things here and deserves a lot of credit. Took over in a tough situation. I think he did have the advantage of the divisional format to allow for some good years (e.g. the 2000 team didn't have to beat a single ranked team to get to 9 wins), but he found some great under the radar recruits and helped them develop. More than anything, Mac made ISU a legitimate choice for decent and good recruits. Prior to that, guys were walking on at TOE rather than take a scholly at ISU.