So glad they are doing better. It depends a lot on the rooster. There is a kind of a rule for at least 10-12 hens per rooster, but I have had flocks with fewer hens. One rooster had 3 hens, but he was an easy going salmon faverolles. I don’t like to advise people to add new birds from other breeders because there can be a danger of bringing in a chronic disease. I prefer to get chicks all at once from a hatchery. But you may need a few more hens. Hard to know at this point. If you do chose to get more, quarantine them for a month to watch for any signs of disease, mites, or lice. Then add them gradually first behind a fence or netting, then have supervised visits. I would add just 1, but 2 or 3 would have better luck being together.