Anyone else out there breeding a landrace chicken?

[ThoughtfulBiped]

Trying to develop a dual-purpose breed of chicken for my homestead which is alert, camouflaged for lush, wet winters and hot, dry summers, broods and forages well, and has good feed conversion (this all goes without saying I suppose).

Looking for input on breeds to introduce, pros and cons, failures and successes etc.

Current Hens; Plymouth Barred Rocks, Buff Orpingtons, Speckled Sussex, New Hampshire Reds, Golden Comets, Black Stars, Brown Leghorns. Had a sweet female Egyptian Fayumi who was taken by a bobcat, luckily saved 6 of her eggs and hatched 5 of them.

Looking to introduce Dark Cornish next season.

Current Roosters; (Black Star x New Hampshire Red) and (Brown Leghorn x New Hampshire Red) a very enthusiastic all white Yokohama and a funky little Frizzle mix just for fun.

How often should I replace Roosters? I know chickens can handle some inbreeding, especially for achieving SOP, but I am not concerned with visual conformity as of yet. Survivability first and foremost.

I know this is pretty open ended but I look forward to hearing people's experiences in breeding, anything helps, even if it is what not to do. Thank you all in advance for your love of chickens and helping me increase my knowledge.

 

[I Love Layers]

Just putting this out there but there are 2 landraces that I have owned that fit your needs, Swedish Flower Hens and Icelandics.
If I were to be doing what you want I would be taking one purebred cock and have him over purebred hens(of a different) breed of the cock, and have numerous different pens with different breed crossings. Then the next breeding season I would take the F1 offspring and breed them to each other. The next season start being very picky with the traits you want and breed for those from there until you get a generation that fits your needs and then that generation would be the actual landrace you started out to create