6" LMB is fine. ANY size is fine, as long as you have the proper sized forage base in place when they go in. Really rich guys can stock 3-5 lbs bass (and the adult BG to feed them); most of us have to grow our own.
One vote for being able to stock 25 to 50 6" LMB this Fall, BG spawning having demonstratively occurred this Summer (freely given and worth every penny!).