I may be in the minority, but I have been culling mine more for type than egg color. I never wanted these things, and only bought the first few a while back at the urging of my 12 year old son, and his obsession with the "Marans Craze". I didn't even consider them part of "my flock".
Since then, they kind of "grew" on me and became a sort of pet project. I believe that my motives and objectives are clear, since I got involved with this, understanding that I have never sold an egg, nor do I have any intention at this time of ever selling an egg. I have probably eaten thousands of dollars worth of omelettes, lol.
I have currently a dozen or so laying hens, both black copper and blue copper running together with 3 black copper roos and a blue copper roo. I also have an additional 60 or so juveniles in different growth stages. My overall egg color is lacking, with the girls averaging 5's and 6's, but I think that some of my birds are looking close to the proposed standard as well as I can understand and interpret it.
My flock is a mish-mash of different lines, and some birds display stronger characteristics than others, as well as deficientcies. The weather is awful today, but I'm willing to take some pics of what's out there in the near future for discussion and critique. I also understand that I have a long way to go, but do intend on exhibiting some of them next spring, when I think that I have something worthy of representing the breed.