I actually agree with Mrs. K.
I think all the mixed breeds will give you to many variables to achieve your breeding goals. And I also think it is very difficult to pick a roo when young because they change so much.
All though leghorns will give you plenty of eggs and are light eaters, they aren't much for meat. Neither are the legbars they are crossed with. And plenty of chickens lay just as well.
It's my understanding that you should never breed a bird that has been sick. And to me, that includes being to weak to make it out of the egg shell.
This may be out of order or unorganized. But if a bird bites when I pick it up, I give it a good peck! Then in the next few days I follow through, picking up and testing. Anyone who continues to bite is SOUP. To me it's an indicator of aggression towards you the keeper. Unacceptable!
Out of the ones you have listed.... Buck or Dodo sound like they fit the bill for DP best out of the given choices (to me). Buck should give you decent eggs and body size, but I am unsure of the aggression level at maturity. I have only had barred and not roos. Dodo should give you a good carcass size as well. I don't have experience with the brahma. I have 3 buff right now and 2 of them are on the menu as they are not my breeders and definitely boys. Funny the first on your list to get rid of was the first I thought you should keep!
There are other things you should look for as well before you decide. Split wing, sprigs, slow feathering or late bloomers (can't tell gender at same age as the rest), just to name a few. Some how, I would think the heavier breeds would fair better in Alaska.
You already have your girls, but I was gonna say you should also consider broodiness. To me, having a hen raise the meat birds so I don't have to provide heat or clean an extra brooder is a plus. And you and I both have enough girls not to have to worry about them all being broody at the same time.
Incidentally I also am a raising DP flock. I have many breeds of hatchery pullets with a Lavender Ameraucana over them. I am not planning to hatch those out. I also have birds from breeders for my pure hatching/eating stock. French Black copper Marans are supposed to be a good DP breed with the darkest brown eggs and flavorful meat. And the breed I am currently in love with, Swedish flower. I keep separate pens for them.
One question is, if you are planning to process your birds anyways.... why not process the ones you are currently considering selling? Even the smaller ones will have some meat on them. People even process their extra bantams.
I also agree with whoever said the chickens may not come out of the coop in the winter. With over an acre of free range, my birds regularly hang out inside even during good weather, by choice! I guess it's a compliment that they are comfortable and happy in there.
One last thing, don't you guys get pretty cold up there? With so many birds in your coop, ventilation is the key to avoiding frost bite (in case you didn't know).
Ok, I lied. 1 more last thing. It's important that you ENJOY the birds you keep! Both their personalities and their eye appeal.
Good luck! (sorry so long, I am passionate about breeding. Would not breed hatchery birds by choice.)