At some point, don't we need to disclose where we think Huggins is rated as a coach before we label him over, under or appropriately rated.
Some things are not ratings, but simply objective numbers. Number of wins would be a prime example. I don't think many people that coaches should be rated based on total number of career wins. Obviously, longevity is a factor and to an extent a large number of wins means little more than the person coached a long time. Now, obviously one needs to be permitted to coach a long time, so not many bad coaches will climb near the top of total wins lists, but it also has a lot to do when people first became head coaches. Huggins and Beilein were young, for example, and are not necessarily now better coaches than people who were assistants for a long time before becoming head coaches and thus have fewer wins at similar ages. They also aren't necessarily better than people who are simply younger than them and so have fewer wins. (or former coaches who retired aafter coaching for fewer years).
Winning percentage, while a better measure, is far from perfect. As some have alluded to above not all positions provide equal chances for success so that differentials in WP don't correspond to relative coaching ability. That also goes for conference titles, tournament success, etc. there are a handful of schools with large built-in advantages, a much larger number with built-in disadvantages and a lot in the middle. (And, even at those in the middle, timing is important. For example, it was a LOT easier to take over at WVU in 2007 than it was in 2002 so meaningfully comparing Beilein and Huggins at WVU requires more than looking at records).
In sum, if you are arguing Huggins is the 3rd best active coach because he's third on the total win list, you will need to defend that against charges of overrating. If you have him very near the top because of winning percentage, without allowing for the advantage he had coaching Cincinnati in relatively weak leagues for a lot of years you could also be accused of overrating.
If, on the other hand you don't have him in the upper echelon because he has only been to 2 final fours and no national titles, you are open to accusations of underrating because he's never been at a school where that was less than a herculean task. You would also be dismissing sustained success across a large number of conferences and a long period of time and changing rules, officiating differences and styles of play.
I'd personally say, he's at least in the top 20.
