Guenther is a good guy who had great relationships with people, but he didn't understand the job.
Really? Come on.
Lots of good things happened under Guenther. He built a lot of facilities and hired some incredible coaches (Kruger, Self, Tiley, Small...). He also made some bad hires, but Zook and Weber looked pretty darn good for a few years. I'd take a repeat of the Guenther era in a heartbeat.
My biggest complaint with Guenther is that he didn't step up to try and keep Self. I doubt anything could have kept him, but imagine Illinois hoops had we kept Self. Of course, you've got to give credit to Guenther for landing Self in the first place.
With respect to his catering to boosters, the times were different. Guenther didn't have TV money and needed boosters to fund the department. Boosters are still important, but their money is a smaller part of the budget today.