No, you did not make a mistake in your selection of breeds. In my opinion people get way too hung up on breed, when breed isn’t all that important. There are breed tendencies, I won’t deny that, but those tendencies get pretty blurred. I have Irish ancestry so I’ll pick on the Irish. Many people have certain preconceived notions about what an Irish person should be like. I did, and when I went to Ireland and worked with Irish people I met some that matched my stereotype. I also met a lot that did not. Each Irish person is an individual and needs to be taken as an individual. Many people have stereotypes of different chicken breeds. Some Barred Rock, RIR, or Buff Orpington will live up to their stereotype, but a lot won’t.
With chickens, the person selecting which chicken get to breed needs to select for certain tendencies or those tendencies quickly get blurred. That is behavioral just as much as physical or production traits. There are very few breeders in the country, hatchery or private breeders, that actually select for behavioral traits. No one can tell you which of your breeds will produce the dominant chicken in your flock and no one can tell you which breed will produce a brute and bully, if any does. You may have behavioral problems or you may not but that is not dependent on breed.
I’m not a believer in magic numbers for chickens whether that is how much space they need, hen to rooster ratio, or much of anything else. We keep them in so many different conditions with so many different goals, different flock make-ups, different management techniques, and who knows how many other differences that no one magic number can cover us all. We are all unique.
As far as space goes, I firmly believe the more room you provide the fewer behavioral problems you are going to have to deal with, the more flexibility you have to deal with problems that do show up, and the less hard you have to work. You can crowd them but that generally makes it harder on you and you may have to make some tough decisions. You may have to anyway but the odds of it being rougher on you go up the more you crowd them. You might follow the link in my signature for some of the things I think you should consider when determining how much space you need.
For some reason this thread got off on roosters. Most hatcheries guarantee a 90% accuracy on sexing chicks, so there is a possibility you might get a rooster or two. Part of that depends on how the feed store handles the chicks when they come in too. Some feed store personnel are more knowledgeable than others. With your black sex links and amber links that should be real close to 100%. It is certainly possible you will wind up with one or more roosters, but not guaranteed.
That 10 to 1 hen to rooster ratio makes for a nice flock, but that ratio is based on the commercial industry where they use the pen breeding method to produce fertile hatching eggs. It has nothing to do with roosters fighting or hens being over-mated. It is purely about fertility and even then just about fertility of hens kept in the pen breeding system. With the way we keep them, fertility depends a lot on the individual rooster and the individual hens. The hens play a part too. A fairly viral active rooster can often keep 20 to 25 hens fertile while a rooster that is not that active might have trouble keeping 3 or 4 hens fertile.
You can have the same problems whether you have a small hen to rooster ratio as if you have a large ratio. You can have barebacked hens with one rooster and 25 hens. Many breeders keep one rooster isolate with one or two hens during the entire breeding season and never have barebacked problems. Some of that is due to the personality of the individual chickens. When I had barebacked hen issues I had a pretty good hen to rooster ratio, but those two hens had brittle feathers. That’s genetic. Their feathers were so brittle they just broke off easily, even if the rooster did nothing wrong. When I removed those two hens from my flock and did not let them breed, my barebacked hen problem went away, even though the ratio was worse.
I always recommend that you keep as few roosters as you can and still maintain your goals. That’s not because you will have more problems with more roosters, but because you are more likely to have problems. With roosters, the more roosters you have the more room you need. This extra room is not about square feet per chicken, it’s about the roosters being able to claim separate territories and minimize opportunity for conflict.
Many of us integrate chicks all the time. The problem is not so much size as maturity level, though a larger chicks is more of a danger to a younger chick. You might be able to integrate those younger Buff Orps without any problems, but the possibility for disaster is fairly high. I’d suggest you keep them in a separate brooder until they get older. How much older? At least until they have feathered out and don’t need the heat source any more. To me that is a minimum. What age you can actually integrate them will depend a lot on your set-up, again the more room you have the better. Again, there is not a magic number for this. I integrate them at 8 weeks, more due to my set-up than anything else. Some people and many broody hens do it earlier. For some people they need to wait until the chicks are basically fully grown. You might want to do a search on chick integration to get different people’s opinions and methods.
You can see there are a lot of different opinions on this forum. A big part of that is that a lot of different things work for different people. It can get pretty frustrating on here trying to figure out which way to go, not because our options are limited but because you have so many different ways to choose from. It’s often hard, but if you can figure out which people raise them a lot like you, then you might narrow your options down. It’s usually not a case of whether you can or cannot do something but how can you do it.
Good luck and welcome to the adventure. You’ll find that it is not as hard as we make it sound.
