good roo??

RIR, by my experience, has been one of the more aggressive breeds to own, but every bird is different. I wouldn't introduce a new rooster to another rooster when they haven't been raised together. My boys who have been raised together since they were babies get along great. The sweetest roo I've ever had was my Silver Gray Dorking. He would let me pick him up and would be content with me carrying him around. All aggressive roosters I get go straight to the pot, so the ones I keep are never aggressive towards me. However he's been the only one so far to let me handle him without any fuss.

 

How many Hens do you have? If you have about 20 or more, 2 roos will fight for which hens they want and then claim different areas. I have had multiple cocks together without an issue. I'm careful to introduce them according to a strict protocol. (quarantine then gentle introduction then introduction in a wide open space).

RIR's can be agressive but the RIR rooster's I've had were really nice.

Silver Grey Dorkings are a great choice, very beautiful and their hens are as well.

Buckeyes are also very nice rooster's, if you partial to a dark bay-near black red rooster.

ISA brown rooster's are docile as well, and so are their hens.

If you prefer a dark colored rooster, Langshans and NJ Giants are also very good choices.


Breeds to avoid because of the other rooster:

Game birds (prone to fighting, noisy)
Bantams that are very small (serama's, Japanses, etc.)
Phenoix
Samatra
Crosses of the above

While the above birds can be sweet as sugar, you can also get one that has a lot of chicken aggression but is the cuddliets darn thing to people. Since you're wanting eggs, you want something that will pass on some productive genes and sizeable eggs. The bantams are cute, but smaller eggs.

 

I disagree. It isn't whether or not they were raised together--rather, it's how many hens you have. If you have enough hens, you won't have friction. None of my boys were raised together. When I introduced a new boy, I simply put him in the pasture. We have a bit of sparring for a few days each spring with the youngsters, but no blood drawn. Just make sure you have at least 9-10 hens per rooster and they'll all get along.

As for breed, RIR have the reputation of being aggressive, but I had a great RIR. I've had EEs, Ameraucanas, Delawares, Orpingtons, Marans... they've all been just fine and non-human aggressive. Get the kind you want, and works for your breeding program (there's no reason to have a rooster if you don't plan to breed). Raise them with respect, not as pets. No scritches, definitely not on your shoulder. You dont' want the "friendliest" chick, those are the more aggressive boys. Get one that runs from you. If he turns out aggressive, cull him. Give him away. Get a new one. I firmly believe that there are more friendly roosters than aggressive ones in the world, and thousands of boys are killed every day simply for being male--and are often given away for free. If the first one doesn't work out, try again!