I keep my peas, guineas and chickens all together right now... I will be separating them about mid winter though so that I can light cycle the peas/guineas into a spring breeding season, that won't happen in the chicken coop as it's light supplemented to a steady 14.5 hours so they are unaware of the season changes...
I let peas and my guineas run together. They have been togeather since they were 2 weeks old. My older guineas still rule the roost! The younger ones steer clear of the peas!