Possible the newer chciks will even out numbers,you may try locking him up until mid summer,or until the younger chicks begin laying.
This is all actually quite normal,escpecially for young guys.The entire process,missing feathers the forcefulness.Wouldnt bother with it honestly unless someone gets hurt.I have a New Hampshire rooster who weighs,I would say seven pounds and is three years and has an urge to mate worsen then any roo I have ever seen.He even goes for the ducks if the hens are too much trouble.But,just like yours he is an absolute great guy.