I made a few mistakes in my analysis above, overlooking conference realignments over the past years. The major mistake was Pitt and LOU both being in the ACC, not the Big East. Brain fart.
But the major point remains, as both of the ACC top 16 seeds landed in the same region.
There is not a single conference with teams spread across all 4 regions. Maybe by design?
The PAC12 won the bracket lottery, with 5 teams total, 3 top 16 seeds in 3 different regions, and 2 more top 32 seeded teams in the same 3 regions. The PAC12 completely avoided the NEB region.
If I were an SEC fan I would be really miffed. Half of their 8 teams are in the NEB region, 3 top 16 seeds, along with a top 32 seed. Three other SEC teams are in the STAN region, with Auburn as a top 32 seed in the PITT region.
My point is other than the PAC12, fans from all major conferences looking to see several conference teams make deep tournament runs are disappointed in the tournament seeding.