I just ordered some chicks to arrive in October, 2 BR, 2 BA, 2 BO, 2 EE, and 1 mystery free one, do you think they'll be okay raised together? I've heard conflicting things about BRs. Have also never heard the 5 and 6 sq. Ft. Thing, have always heard 4 for inside, 10 for outside (and in commercial, standard is only 2 inside 4 outside which is obviously way too little) but have heard more is better if possible so it's interesting.
You've got pretty big breeds so IMO if they're confined/penned then 6 sq ft/per bird with logs, swings, perches, a dust-bath container, old chairs, tables, whatever, for something to do - but if allowed some foraging in the backyard then 4 sq ft/per bird of coop space is adequate. To start we only had our 2 Silkies for 4 weeks in a 4x6 coop and quickly realized even these littles needed more room to be entertained so we let them out of the coop at 6 a.m. and they foraged around the yard all day and put themselves to roost about 1/2 hour before dark. For daytime protection/hiding/snoozing in the yard we added a popup canopy, a couple low plywood shelters set on cinderblocks, and kept adding large recycled dog houses around the yard for them and they use them ALL! We are up to 4 hens now and their new coop is 4x4 with a run below and an additional 4x4 run added on. My girls love the coop and sometimes hang in the run or just go in it to lay eggs - but they prefer the wide open spaces to dig for bugs, dust-bathe, scratch for seeds and search for budding grass/weed seeds, etc. Your birds will grow up together as a flock and they'll figure out the pecking order. Your BAs and EEs might be closer to the bottom of the pecking order since Ameraucanas and EEs would rather avoid conflict at any cost and prefer to flee than fight. BA's are somewhat gentle giants but should be able to stand up for themselves because of their sheer size to not get bullied much by the BR and BO who usually seem to take over dominant positions. I'm glad to see you don't have bantams in the mix. My personal opinion is that littles not be mixed with LF where they have no chance to hide from assertive larger fowl. You'll get to know your birds so well you'll know in your gut what will work for them - and you! Enjoy!