It depends on your set up. If you have the means to keep her seperate and the chicks can avoid being squashed by other stupid chickens, then for sure! It is WAY less work for you, and the chicks/hen are happier and healthier.
I would love to have a hen raise some babies here. Would love to see my kids have this experience. It was always fun growing up to see chicks running with the hens.
Um yes if you allow them to go broody and raise their own babies then you don't have to worry about buying more because you have fuzzy butts being born right on your own farm, what could be better?