There are no rules when you break away from the NCAA and they will. So no required records just division finish and tie breakers. It will no longer be about making sure there is a top team in your league. So no they wont need bottom feeders.
Ohio State, Michigan, USC, Oregon, Alabama, Texas, LSU, Oklahoma, etc. are not going to put themselves in situations where they only win a couple games a year. The fan bases will not stand for that. Even if they all make a “playoff”.