I think put out some inquiries into the "they're too high up the food chain" coaches you mentioned, but no further due diligence needs to be done with Petrino-he's done that legwork already with his own actions. Maybe I'm just projecting my personal feelings here, but I just don't think the fans in the state of CT are willing to bring in a proven dirtbag, even if it means winning.
I agree most strongly with some other posters who say take a shot on a young, charismatic coach who has proven he can win on the 1AA or even D-II level. I'll roll the dice with that. I didn't used to think that way, but I've come around to that. Not out of desperation, but I think a "non-sexy" name in the media that still has the personal presence to impress recruits and their families in their living rooms, who knows what he is doing as a coach with a proven track record, can get us to the next level at least. There are tons of great coaches out there who can coach the crap out of this game, even if they aren't on national TV every week. I think a lot of Coordinators for big schools are "stars waiting in the wings," but for every one of those, there are at least as many Coordinators for big schools who are respectable, solid coaches overall but look like all stars because of the caliber of athletes they have at their disposal.