I agree with DMRippy, the blue male looks to be a cross with Birchen. Your Black Copper pullet is way overmelanized, not a speck of copper coloration on her hackles and very dark eyes. She also is clean legged from the photo. I would hesitate to use her but if you do, make sure the male has nice heavy leg feathering and good color. You will be looking at several generations to lighten up the females using that one, I think. The BCM male you posted looks fairly good but has something funky going on with the blade on his comb. Lots of little points on it. Not sure if those would be considered sprigs or not. I don't think they are, just could be carnation comb influence. It is also useful to take a photo from above the bird so we can see how wide they are. You want a nice wide back that does not taper towards the tail. Also post how old the birds are. The blue pullets are a bit out of focus, but the first one looks nice. The second one looks to be narrow in the chest. You want a nice rounded breast when viewed from the side, she looks like a triangle. Third one needs photo from the side to see her profile. She looks a little pinched in the tail. The one thing that strikes me about all of them is their heads look small in comparison to the rest of the bird. I think this is a common problem. Also, did the blue copper pullets come from the same breeder as the male? If so, I'd be worried there might be Birchen in their background as well, although I don't see it in these pullets.
Everybody, remember when posting photos for critique, you can only see so much from photos so give us the best photos you can and include side view, top view, front and back. Close up of head is also useful and one shot needs to include the whole leg/feet so we can see the feathering there. And remember: the breed is always spelled with an "s" on the end even when singular: Marans
