Hi
I always want to encourage someone to get geese
but this combo you are considering has lots of issues you should know about first.
First, a tractor set up would work but it would have to be pretty big. Two geese, seven ducks and seven turkeys means a LOT of poop. My full grown tom turkey could poop an orange sized turd (well, tangerine). Geese and ducks poop about every ten or fifteen minutes. If they are mostly free ranging, this will be OK, as goose/duck poop is loose and you can hose it into the grass once a day. It is still raining everyday
here in western WA so the poop is dissolving overnight.
If they spend most of their day outside the tractor, you'll still have a lot of crap to deal with.
Ducks and geese MUST be brooded entirely separately from those turkeys, too. Turkey poults are very fragile, need heat longer, and will not tolerate the mess and moisture the geese/ducklings will make of their brooder. Turkey poults must never get wet or chilled. It's hard enough to keep turkey poults from dying in that first week or two as it is.
Goslings/ducklings will play in their waterer, and their food, mixing the two unless you separate them by a few feet, and make a terrible mess every two hours or so. SOme folks feed them a certain amount several times a day rather than free feeding, which cuts down on the mess.
Goslings/ducklings in summer months will only need extra heat for a week or two. Yet they too must be protected from getting soaking wet and chilled for at least two weeks. Without a mama, they lack her oils in their down and soak water like sponges.
Goslings grow like Baby Hueys, and will outstrip the ducklings and turkey poults. They are bossy and pushy. The ducklings (depending on type) may get stepped on, unless there is plenty of room in the brooder. They will get along fine with the ducklings as their "flockmates" though, and will stay close even as adults.
So you have some thinkin' to do.
If your new poultry and your present chickens are able to see one another every day, say through chicken wire, they will be familiar and able to free range together with little problems. Well, there will always be SOMETHING, because these creatures do not naturally co-exist, but familiarity from hatch will help. The chickens will pick on the little ones until the waterfowl get bigger and realize it. Sometimes turkeys fall in love with chickens and can hurt or kill them trying to mate. I have a chicken in my bedroom for the last six weeks with no skin on her back (healing very well) from the tom turkey. He became so aggressive I had to rehome him to another persons, er, freezer
Hope I didn't ramble to much and gave you useful advice and stuff to think about