German New Hampshire: how many hens does one roo need

[Sylverfly]

So I managed to hatch out 3 German New Hampshire out of a dozen eggs, I lost power and everything else during incubation so I feel lucky that I hatched any. Buts its been a few months since the hatch and I ended up with 2 pullets and a little roo. They are very pretty already and I have hopes of incubating the eggs as soon as they are less pullet eggy. But I'm thinking the rooster will put those 2 hens through heck if he only has them for a year. I don't want to add more hens because the only ones I could add lay brown eggs and I'll have no idea what I'm hatching when I collect eggs. But I also hate the idea of keeping him in a cage for a year. But if I want more chickens from these guys I can't see what other options I have. Any ideas or experience you guys can share would be terrific.

 

[auburn]

I have a friend with only two hens and a rooster, but it's worth noting he's rather clumsy with his girls. He's also not top dog, one of the other hens is, which tends to keep him in his place. It's been about half a year (girls are a little over a year old, rooster was hatched last December) and things are mostly fine, though the one submissive hen is getting a bit of a bald spot behind her comb (which is actually an improvement; he used to bite her actual comb when mating her instead of the feathers on her head because, well, as mentioned, clumsy boy

).

Also worth noting that her hens are Barred Rocks and that the rooster is a Rhode Island Red and ISA Brown mix.