Baby chicks with older chickens

[Jesus loves me]

Hello! I have 6 laying Brahma hens they will be 1 years old in April, and I was thinking about possibly getting a couple more chicks this spring and maybe a different breed. They would also be used for egg layers and was wondering if it would be smart to get some more this spring or to hold off another year and wait till the Brahmas are a little older? Just because if the chicks would get picked on, I know they say that Brahmas are supposed to be good mothers but didn't know if I should chance it or not? I was hoping I would have gotten a rooster with the Brahma hens so I would have fertilized eggs, and they could possibly hatch their own chicks out but that didn't happen. Wondering what ya'lls thought were? Also, if I did get chicks what would be a good breed for egg production and docile temperament? Thank you!