Considering who's running things in the NCAA (it's the Power 4), it's inevitably going to be the 68 teams in the Power 4 getting all 68 teams in + 27 Automatic Qualifiers (assuming that the PAC-12 is fully dissolved and the Power 4 doesn't need AQs anymore), plus maybe 5 at-large bids from the BIG EAST, Mountain West, and occasionally the A-10. The top 32 seeds from the Power 4 automatically get into the Round of 64, and then you do some sort of rock fight among the bottom 36 P4 teams, the AQs, and the handful of at-large bids to get into R64.
It'll be annoying as shit, but it'll make the monied and powerful people happy and that's what matters.