another problem with the "top 100" cutoff or whatever:
you keep t1 and t2 schools, but eliminate all the t3s and t4s. right now, the number of law schools is dictated by the market for a legal education, which is in turn dictated by the market for legal services. what happens if you make the market for legal education less competitive by restricting the supply? the cost of school itself skyrockets, as people who are capable and willing to go to school are given fewer alternatives. the people at the margins who still greatly value that law degree, instead of going to a T3 or T4 with a scholarship and getting some consumer surplus, end up paying more to go to the top 100 schools. this is overly simple, but supply and demand analysis tells you that you can't reduce one thing (the number of law schools) without drastically affecting another (the cost of attendance).
i guess this is great if you want to increase the "elitism" of the profession, but the best thing for society is to let the market dictate the number of schools and for the bar association and other governing bodies to make sure potential students understand the probable value and risk of their investment.