As RR said, it just depends. I keep multiple roosters, usually two for each of my three breeding groups, and they must all get along. For me, human aggression or injuries to hens or pullets are cull points, and I after years of waiting to see if an individual cockerel will 'improve' his...
If you have one that's polite, that will be wonderful. I agree that keeping them as long as possible will make decisions easier. Any that behave badly, or who have physical defects, can leave any time. If this group all turn out well, how nice! Then rehome one or two so your pullets are also...