no one really knows what the answer is
if you really think about it, you realize what a crapshoot it is. there are certain qualities you can look for in a head or assistant coach, but there is a lot of luck involved too. for example, one of the hot names out there recently is Tom Crean of Marquette. i'm sure he's a fine person and he's done a nice job at Marquette, but does he really deserve a shot at leading Kentucky, one of the top 5 programs in the country? (the others are UCLA, Indiana, Kansas and North Carolina. that's it. that's the list.)
anyway, my point is that Tom Crean was a well-regarded assistant under Izzo, and he has been to the tournament 4 times in 8 years at Marquette. but 2 of those years were with Dwyane Wade, who Marquette was lucky to get because many big schools stayed away due to academic concerns. Wade was also recruited by Illinois State, who at the time was coached by Tom Richardson (i've never heard of him either). but let's just say Wade goes to ISU and leads the RedBirds to a first-round upset or two. Richardson becomes a hot name and gets a bigger job and Tom Crean is probably fired by now. so how do we really know who is the better coach?
Bill Carmody was 92-25 at Princeton in four years. John Thompson III was 68-42 at Princeton in four years. i don't know anyone that would argue Carmody is a better coach, but maybe NU really is just a black hole program who will always be in the bottom 3 of the Big Ten. sounds depressing, but we need to be damn lucky with the next hire for NU hoops to be anything else.