Guineas are considered in the gamebird class and gamebirds should not be kept with chickens. Chickens carry diseases, that even though they show no outwards signs of, can kill gamebirds. So keep the guineas in their own space. Pea's are very large birds and really need their own space. All of these species have different feed requirements as well. But yes, goats and chickens can be kept together with a good amount of harmony.
Good luck with all your projects and welcome to our flock!
Welcome to BYC! I second TwoCrows comment...that is a lot of livestock in the same area and the chance of disease increases sharply because of that. Keeping chickens, turkeys and ducks is doable, but game fowl are different and probably shouldn't be housed together. I also keep goats separate because they tend to climb on a lot of stuff and break it, and I have heard from chicken/goat owners that goats will dominate feed, and that is a problem. Furthermore, it would be tough to provide proper nutrition to all those animals, as they will eat the same feed, and I am not familiar with a product that is made for all of the animals listed above.
I agree, that the goats and chickens will have squabbles over food. Mine were cohabiting fine, but I had an acre, one goat and her 2 kids and 3 chickens. They rarely ran into each other. My plan is to sell my goats and give the pasture fully to chickens. I liked the goats, but they didn't work well for me. I mean they cleaned up the pasture ( I had the timber cleared off and lots of hedge grew quickly) but I really didn't like the upkeep. I like chickens. As soon as the kids are old enough I will sell them. Anyone want some mixed Boer Billy goats and a "some sort of goat" awesome goat mama?
Thank you all. The coop is actually in the process of being built I'm hoping to make it 30 feet wide and 60 feet long. I was gonna make it plenty big enough so they could all move around. I was planning on having two pygmy goats, maybe 10-15 chickens and 8 peacocks. I'm a little iffy on the guineas only because I know they like to roam, I know peacocks do too. But I've always wanted one. However guineas are good for eating ticks. But I was hoping of I put them in a coop I could keep them used to their new home and if they got out they wouldn't go to far.