Chickmate, there are people on here with far more chicken experience than me, but I have many different breeds together and have never had any problems. I do have a process I go thru when I introduce new birds. I normally put the new birds in a wire dog crate out in my animal area when my other birds are free ranging. I then move the crate into the chickens run in the late afternoon. Once the other girls are roosting for the night I open the dog crate and they normally go right in the coop with no problems. When I purchased my first chicks the guy told me I shouldn't mix standard size with banties just because of the size difference and th smaller ones may get picked on. I like having a couple of many different breeds. I think I would get bored if I only had one breed to look at. You should post some pics of your coop so we can all enjoy. Good Luck