My Dark Brahma is incredibly sweet and has NEVER hurt or challenged me once. I don't know how, but I got a perfect rooster. I know that's not one of the breeds you have listed, but just my little story.
I had had 3 roosters living together for almost a year, with less than 20 hens as well. They never drew blood from each other or fought more than a peck or small squabble, and the hens were fine with it (they probably bossed the boys around more than the other way around). So I think you could keep 2 if they grew up together, and so long as they never cause trouble, whether with your hens or each other. I've had at least 10 or so roosters over time, and only kept ones that were useful to me, so that's my advice: keep only if they're useful. I've kept one because he was gorgeous for showing--even though he gave me several welts over time--and I've kept others because they were good to/for the hens, or like my current roo who is the sweetest chicken I've ever seen--even more so than my hens.
But out of those breeds you have listed, I think barred rocks have been known to be very friendly roosters--or at least I've seen some on the internet who made excellent, friendly pets.
I had had 3 roosters living together for almost a year, with less than 20 hens as well. They never drew blood from each other or fought more than a peck or small squabble, and the hens were fine with it (they probably bossed the boys around more than the other way around). So I think you could keep 2 if they grew up together, and so long as they never cause trouble, whether with your hens or each other. I've had at least 10 or so roosters over time, and only kept ones that were useful to me, so that's my advice: keep only if they're useful. I've kept one because he was gorgeous for showing--even though he gave me several welts over time--and I've kept others because they were good to/for the hens, or like my current roo who is the sweetest chicken I've ever seen--even more so than my hens.
But out of those breeds you have listed, I think barred rocks have been known to be very friendly roosters--or at least I've seen some on the internet who made excellent, friendly pets.