It sounds like SenecaTinsely gave the exact same advice regarding the coaching circus that I would have, and actually followed myself last year. If you ever get to a game in Ames, you'll learn that "drink heavily" is basically the only way Cyclone fans have gotten through, well, our entire existence.
Mac was a good man, but hit his limits. He needed to go. The way he continued to choke away the North in the exact same fashion, it was clear he did not learn from the mistakes he made on the field, and he likely never was going to.
Look at the Brewster situation this way: if he goes, good. It sounds like you guys aren't too thrilled with him right now anyway. It gives you the opportunity to snag a Butch Jones. At this point, his staying might actually be worse for everyone. That's definitely the way the Chizik thing felt shortly before he left. You KNEW he was looking to get out, and it was going to be awkward if he stayed.
You guys seem like good folks, and one of the few teams in the Big 10 I'll cheer for (NW and Purdue are the others). Hopefully this turns out for the better.