I've had success with pairs, but it depends on the male. I originally had a 7:1 ratio from breeder birds I bought fall 2 years ago when a breeder was shutting down for the year. I had no idea how old the birds were, but they slowly died of what appeared to just be old age. This April I only had 3 females left, so I hatched out their eggs so I had replacements. One female died while the eggs were incubating, another shortly after. That left me with one male and one female, and 18 teeny new hatches. The pair did fine together in a 2x4 rabbit hutch, would make a nest hole and sit together in it, and never fought or had feather pulling issues.
Once my babies were about 4 weeks old and able to be separated by gender, they moved outside. I had a large hutch for the females and a large hutch for the males. One of the males was smaller and picked on, and I had turned the one female hutch into a duplex and split up the females so they could spread out, so I put the little male in with 3 females. One female claimed him and would fight the other females to get them away from him, so I put the two of them into a hutch by themselves and they did great. I think he was just happy someone was fighting for him instead of fighting him.
Right now I've got the original male in the cage with the 3 females (after his partner died) and he's doing great. So I've got 4 females in one hutch, 3 girls and 1 male in another hutch, the pair together, and 7 males together. The boys do pick on each other occasionally so they've got the biggest cage with hiding places. There's a couple of them that are aggressive towards the other boys that I wouldn't put in with the girls, but the gentle ones that are in with them now do just fine 1:1 or 3:1. If yours are growing up together and are used to each other, I'd bet that they are going to be fine. And if they are fine, I'd personally be hesitant to add in more later for fear of the female being protective or the male getting over-excited and more aggressive. Good luck.
