this is not a rule suggestion, but just a general suggestion. I would like to see pics of the actual eggs your hens are currently laying also, ot the darkest egg that was ever laid in your history of chicken raising, as egg color is a big deal in many breeds, and so is the size and shape of the eggs.
I have had nothing but fun and mostly great outcomes from online buying and swapping, but some people have shown me some skinny ol' pointy at both ends, poopy covered, wrong color eggs that they have gotten from online dealings. If you showed what your eggs look like, along with the birds, man, this thread would be the BOMB!! I have two BBS marans that lay VERY BIG, NICE eggs, but the color is too light for serious marans breeders, but still, someone that just wanted some nice, extra brown XL size egg layers might want their eggs... I know I do, I am trying to hatch some right now. I'd like to have a dozen of them, even though they are not technically even marans.