Toughest regional?

[XaulZan11]

It's easy to name the top 3 teams at a regional and cite it as the toughest regional, but I think the depth of a regional is equally important. Midwest was mentioned a couple of times in this thread. While it probably has the biggest group of elite teams at the top each year (16, 71, 111, 1625, featuring appearences within the past 3 years by 1114, 217, 118, 148), its been extremely shallow the last two years to the point where the top 3 seeds almost have first round byes.

Wisconsin and Midwest both the same week has really hurt Midwest's already lacking depth. 148 is a new addition but 45, 118, 1675, 1732, 2041, and 2826 won't be there this year.