Two of expansions proponents, Jay Wright, head coach at Villanova and Jim Boeheim, head coach at Syracuse seem to think a bigger tournament is better. Maybe that's because they envision an easier path to glory than the current system? Both Villanova, a #2 seed, and Syracuse, a #1 and a favorite to win the whole dance, were knocked off by underdogs: #10 Saint Mary's beat 'Nova in second round after they struggled in a double-overtime victory over the #15 seed and 'Cuse lost in the Sweet Sixteen to #5 Butler.
There are many other reasons against expanding the field. For one, it would completely eliminate late season competitiveness down the stretch of schedules and into conference tournaments. In the current system, the teams on the bubble of making the tournament are the most exciting to watch; they scrap and battle at the end of the year trying to impress the selection committee enough to earn a bid. Take Michigan this year for example. We weren't even close to the bubble entering the Big-10 Conference Tournament. But, every conference tournament winner gets an automatic bid to the tournament; it was our last and only chance to make. So after dispatching Iowa in the first round we went against #7 nationally-ranked Ohio State and played inspired basketball giving them a run for there money and positioned ourselves to win until this happened. That hurt just linking that. Regardless of my pain, Michigan would never have played with the urgency that we did in that game if the tournament was 128 or even 96 teams because we would have already had a bid locked up. We would have had nothing to play for.
Additionally, who really wants to see the 128th or 96th best team in the nation, who are under-.500, play? Let alone get smacked by a far superior opponent. Giving high ranked teams byes into later rounds of a larger tournament is also stupid. The appeal of March Madness is watching even the best teams have to win night in and night out, which allows for the upsets and Cinderella runs to happen. Giving byes is like saying you don't like upsets because it directs delays the inevitable upsets until later. And if the NCAA even cares about athletes and their academics as they say they do, a larger tournament would keep student-athletes out of the classroom for even longer.
If it ain't broke, don't fix it.