We are getting chickens for first time. A small, laying flock ( 5 to 7 birds). As we are in cold weather area, large breeds are our preference. A mixed flock is the plan, just because they look so nice and its great seeing the differences. Between the barred rock, orpingtonz, Australops, and Brahma, etc. the maturity rate is from fast to slow. Will this growth rate be a problem when chicks all brought in on same day? Or is the difference nothing to worry about? Thanks for the help.