I knew what you meant. With my rooster, I got rid of the ones that were darker... maybe should have kept them. I personally like the French Standard... when I first started looking with this I read the French Standard and it said you could have some red speckling on the breast.. they say the American standard should be black. That is a big difference.
Actually the American SOP states you can have up to 10% copper on the chest. And I'm sure they base it of 10% of the total surface area that should be black. Most breeders believe if your using a male to produce females, a little color is good to add color to the females.
The problem with young males is, you have to find a developmental balance. It would be best raising your chicks and watching the stages your line and birds turn into. They need to develop at a steady pace for color. They should gain color to quickly or remain to dark and not get enough. Most breeders on here will say that when chicks grow and start throwing copper very early its a sign they will get to much when they are adults. But the best thing I would say is raise them, take notes, see what issues your line has and make changes. If you get to much copper to soon, then changes need to be made. That goes for everything.