David Friedman suggests that, instead of limiting a football team to 11 men, you allow the team as many men on the field as they’d like, with the constraint that their total weight be below some 2400 pounds. It’s an interesting idea.
Commenters suggest the related idea of limiting the total height of a basketball team to 30 feet. Then we’d find out right away how tall these players really are.
I’m not saying these ideas are perfect, but they’re interesting.