O'Leary was the best actual football coach we've hired since Lou. Yeah we muffed the vetting process and then went full holier than thou in firing him, which was a huge overreaction IMO, but I believe if he had ever gotten the chance to roam our sidelines he would have had great success.
Kelly was the right hire for the time and has actually done a lot of really good things for the program overall and improved the overall talent level significantly, making this no longer the bare cupboard destination it was viewed as not too long ago (he would probably make a really good AD). Unfortunately he just isn't quite good enough at the game day stuff to compete with the big boys which is what you need to cut it here...as much as I think its time to move in another direction from him at HC, I do not think he was a bad hire.
Davie, Ty and Weis were really bad hires and its a bit concerning how those guys could have even been considered, which is why a lot of people (even those who aren't happy with Kelly) don't want to see Kelly go, because they are terrified that we'll make another hire like those three. I share this concern, but I believe this is just the risk that comes with the business of trying to be great...if you aren't willing to take the risks required to improve because you're afraid of failure then you might as well just pack it in because you've already conceded failure by not making the attempt.