Despite getting crushed by Clemson, Ohio State was a good team last season, and they'll be good next season.
Michigan will lose a giant amount of talent, but it has had great recruiting classes last year and this year, so it could still be good next season. It depends how good they are at getting new guys up to speed.
Penn State will not be a sleeper next season now that people have seen how good they are.
Michigan State can't be as bad next season -- I think nowhere to go but up for them.