In my beekeeping classes, I teach how to work WITH the bees not to make them do anything but to provide what they need so they can do what nature drives them to do. Success with peafowl is to provide them with a happy environment, good food, clean water, and a watchful eye to spot potential problems. Do this and nature will bless you with healthy offspring. Their environment should be spacious and safe with no distractions to worry them. The feed should be high in protein and made for their species. Ample water in clean bowls that they can not walk in. And you must be able to spot problems before they present themselves as a danger to the birds.
That being said, an older cock over a younger hen will produce more eggs than a younger cock would.