I raise peafowl with chickens (many breeds, including "game" type chickens) all the time. The peafowl are the undisputed rulers of the coop. The chickens don't bother the tailfeathers at all. I have raised the two species together for about 20 years.
It is not necessary to have a pair, but they will be happier if you do.
Of course, the males don't acquire their full tails until they are 3 years old. The hens will very occasionally lay eggs at a year, but they are usually infertile. Second year eggs will be somewhat fertile, but the hens don't reach their peak fertility until they are 3 years old. They are decent setters and good mothers. They are also very hardy birds, roosting in the branches of the tallest trees through all types of weather.