I think you would be happiest with a meat flock and an egg flock. You are talking 52 chickens to butcher to meet your goal of meat every week. And that is a very, very ambitious goal. I would highly recommend that you start smaller, and take the approach that you reach your ultimate goal in about 3 years, in that time you will gain a lot of experience if you have not done chicken before.
What I would recommend, is to start with 6 egg layers and 6 meat chickens and 6 dual purpose chickens. Meat chickens grow very fast, and you would have something to butcher in 8 weeks. These birds grow very fast, and will probably need their own pen. Butchering 6 chickens will give you experience and even with help 6 chickens is a bit of work, without overwhelming you. You can figure out the freezer room, the knives to use, how you are going to get it set up. Almost always, after you do a few, you start to figure out ways to make it easier. Then you could repeat, if you liked this. These would be very tender birds, and not need a stew pot.
Your egg layers will start making eggs at about 4 months, your dual purpose hens will grow a bit slower and start laying at about 5-6 months. The dual purpose birds, tend to go broody, such as BO. They don't lay as much as the egg layers, but mine have always laid well enough. I find the dual purpose roosters ready to butcher at about 5 months, so they will be coming out of your flock. You can run the dual purpose and the layers together.
Even though you have 18 acres, you will still need a coop and run. There are times that you need to keep your birds in a totally enclosed run. If you are gone for a couple of days, or if predators find you, and they will, it is good to lock up your flock out of their reach. If you plan to free range, you need to plan on losses, and if the loss is your food, that really bites. So that even if you have acres, you are still going to be limited by the size of your coop and run.
Generally I plan (but I use that word cautiously, as the coyotes and I make different plans) to have 3 generations in my flock. 2years old going on 3, 1 year olds going on 2, and new chicks. In the summer, when the days are long, and mine spend most of their time free ranging, I let my numbers build, chicks are hatched, and little. As fall comes on, I bring my numbers back to a minimum flock, so as to keep my feed bill down when the birds are the least productive. So I cull roosters, and older birds. This gives room for the chicks that are now getting bigger. It is not static. I do raise my chicks with broody hens, but you will often times loose some chicks that way. It is the survival of the fittest. I recently hatched out 7, and in the first 3 days, lost two of those. I think the remaining five will make it, but the natural way is kind of ruthless.
I garden and have chickens, and I have never come close to sustaining my family, but we eat a lot off of my work. Sometimes it is better to start a little smaller, not such a huge investment, not so overwhelming.
my 2 cents,
Mrs K