Hi! This is our second year of guineas and I absolutely love them
I hope I can be of help in answering your questions.
1st: We keep our guineas and chickens together and they live great together. The guinea cocks will occasionally chase a rooster for a little bit, but then again the roosters will occasionally try to mate a guinea hen. Our guineas show absolutely no aggression or bullying towards our roosters or hens. It may depend on your guineas/chickens. Do you currently have chickens? I assume you do and then it would probably be easiest to integrate guinea keats into your flock. (Although I wouldn't suggest letting the keats roam in your chicken flock until they're at least 10-12 weeks old) They should get along fine together.
2nd: It depends on what you mean by "docile". Unless you particularly tame them, you cannot hold/catch them easily. You can train the guineas to come when called I assume. Ours don't exactly come when called, but if they see one of us with a bowl or container in our hand then they come running. Personally I think guineas work best free-ranging. I've never used a chicken tractor so I don't know how that'd work.
3rd: Are guineas noisy? I'd have to say yes although I like their calls. All of the keats will be extremely noisy their first year. Once they "pair off" they tend to quiet down a bit. The hens are chatterboxes and talk buckwheat all the time. (This does vary per hen of course, some are very talkative and others are rather quiet) The cocks are not so noisy and generally only talk if their sounding the alarm or calling the hens for food.
4th: Yes, personally I believe guinea eggs to be more nutritious then chicken eggs. Why? Because they get out and eat more bugs and grass seeds. Guinea eggs are generally smaller than chicken eggs but they do vary in size.
5th: Err, this would depend on how you let them range. If their in a chicken tractor then I guess you could clip them. If you let them free-range, do not clip them. A guineas wings are it's safety. If a predator is chasing the guinea it will simply fly into a tree.
6th: I've never killed/eaten a guinea before so I don't know. I'd say at least 3 lbs for your average hen. But I honestly don't know.
I hope I helped