Did she start incubating all the eggs at the same time, or were eggs added to her clutch after she began sitting? Does she live with other hens in addition to the two roosters? Other hens actually tend to be more aggressive towards chicks than roosters. But there are exceptions to every general rule, and your broody's rank in the pecking order will help predict if there will be any trouble. Since you are concerned the chicks will be harmed, you could block your broody's nest box from other flock members the day before the eggs begin to hatch (day 19 or 20), then move the family to their own private space after all eggs have hatched. A broody sacrifices all her normal chicken activities to do nearly nothing but incubate her eggs for 3 weeks, and I feel sad for the broody to remove all her chicks as they hatch. But a risk of them being killed by other flock members or predators is no good either, and if raising them in a brooder is safer for the chicks as well as easier and less stressful for you, then yes,it sounds like a good plan.