I have all my buttons living free range in my aviary. I have 87 and they all get along just fine. I had to do another hatch though so I knew they were happy.
The best way to know if your birds are getting along and are fine with their situation, is to hatch their eggs! find out how many hens you have and take that number x2. Then hatch those eggs. The girls will tell you if they need more boys or more girls. If all the eggs are at an even split (males/females) when they're adults, the birds don't need anything else. If in the hatch there is about 1:2 or 1:3 or so on with males/females are females/males, your girls want more of whatever there are more of. But if there are only a few more boys than girls in the whole hatch, you're fine.
I have noticed that they like to live together. They get along awesome! but they are still monogamous. However, some hens prefer to be a couple with a male.
I know with my crew in the aviary, they team up when they want to hatch a brood. None of the boys help except to bring food, but five of the girls choose a location and take all the eggs in a 4 foot radius that are laid in that area and put them in the nest and there will be two girls on the nest at a time, just rotating shifts so they can eat and drink.
Also, for those of you who think that plucking is a sign, it doesn't matter if you have 10 or 100 buttons. It is part of their pecking order, and once they start, they don't stop. I did a whole rehatch and rehomed all the other buttons and they were fine for about a month. I was down to 2 square feet for each bird and when the boys chose where they wanted to be, they picked each other and the hens caught on and started doing it too. The only time you should be concerned is when they are beating each other or killing each other. If there is blood, check the gender of who is bleeding. Either that one isn't getting along and should be separated, or if there are several of that gender that are bloody, you have too many of that type. Take out the ones at the bottom of the pecking order (more bloody) and do a hatch. let your girls tell you! they choose what they need.
best of luck to all of you!