there are 120+ college teams, with 80+ players, about 20 graduate each year, so that's about 2400 potential players available each year.
32 pro teams, 53 players each is 1696 players.
so you could literally fire the entire league and re-staff it in a heart beat.
quality of play you say? you watched college games Saturday. same players.
bet you wouldn't even notice the change.