This sounds a lot like I was a few years ago. And for the most part, I agree with every thing in the other posts, so let me see what I can say that is new.
Blackhead. Some one in your flock has to already have it in order to pass it on to the turkeys. I live in SW Missouri, and (thankfully) it is rather rare around here, so I have never had a problem. Ive been doing this for several years. The first year, we got day old chicks of turkeys and chickens and that was how we started out flock. All of them together in the brooder and all the way out into the coop. The turkeys got bigger, but none of them were mean. The first year we only had BBB and the free ranged with the chickens and came in every night. They didnt try to fly up in the trees to roost. Getting over the fence was all they could do early and when they go bigger, walking was a chore, lol! Good birds.
When we introduced more the second year, there were very few problems. Again, we got chickens and turkeys. The chicks help teach the turkeys how to eat and stuff, or so they say. Guess it worked for me. Had the typical new bird issues, but once the pecking order was established, there were not fights.
This (last) year we got both BBB and heritage breeds. Again, no problems. Well, I did put 2 geese in the mix and that changed everything. Dont put geese in there! They starved most of my turkeys to death before they were 2 weeks old.
We got our turkeys in early June, and the Reds dressed at about 12 pounds for thanksgiving. Guess that is a good sized bird, but the BBB were 22-24 pounds and the year before, thanksgiving dinner bird was 32 pounds. So there is a difference. Not in taste or quality of the meat though.
I got the heritage breeds because I want to try breeding and raising my own this year. I now have 3 hens and 2 toms. I culled the ornery ones and keep the biggest, not the prettiest. I think Ill do ok. I imagine Ill have turkey poults running out my ears!!
Im planning to build breeding cages so I can determine the parentage of the poults. Three cages. And I would definitely separate the broody hens from the flock. The tom and the chicks is a perfect example. Mom doesnt need dad after they hatch.
Good luck to you, have fun, keep notes or a diary so you can go back and check things, You will never remember it all, and it has been really nice when I can go back and find some thing out, and a bummer when I didnt write it down. Simple things. Experience is the best teacher.