I think Miles would listen. He's got as big an ego as anyone out there and he could be the hero riding in on a white horse to rescue the sinking ship and return them to the days of Schembechler. He's got a good team coming back next year and is assembling a good recruiting class, so I can see why he would want to stay. But I don't think it's unreasonable to think he'd listen. Everyone has their dream job. Some guys are strong enough to resist the temptation (see Urban Meyer and Notre Dame), but most aren't.
I also know Peterson from Boise State has pretty much said he plans to stay there, but I'd definitely make the call and try to see if there's anything that could be done to sway him. It's a longshot, but if Harbaugh isn't interested, he would be a huge hire. Same for the guy from TCU, although I doubt he's gonig anywhere either.
The other guy, another big time longshot, would be Dan Mullen. He's probably not interested in leaving, but I think some assume he's an SEC guy. He's from Pennsylvania and was with Urban Meyer for a long time, so he's not like Muschamp who was clearly an SEC guy. He's got MSU on the right path, but he's always going to be recruiting uphill down there against the likes of Alabama, LSU, and Florida. He's much more likely to get big-time athletes at Michigan than at Mississippi St. MSU's not a bad job, but they're never going to be a consistent SEC powerhouse, IMO. He has a much better chance at playing for a national championship at Michigan than MSU. His offensive style would fit Denard Robinson, so he wouldn't need to completely retool the offense.