I wrestle with this same thing every time I incubate. You just never know, but I think a lot of it comes down to the temperament of your roos and making sure there is enough space for everyone. I have two coops (a big one and a medium sized one)joined by one outdoor run. The two coops help if you have more than one roo especially in winter when they are more cooped up. I do not tolerate an aggressive roo towards my flock or me, been there, done that. I also try to only keep breeds that are known to be more docile. You will just have to watch and wait and see how it plays out, but be prepared with a back up plan in case things go south. Several years ago, I came home one day to find one of my roos badly gutted from a spur to the belly when before that had been peace between the three of them. It was bad enough he had to be put down. It is easier to just have one roo but I hate to butcher if I don't have to, so I just cross my fingers I have good boys.