@wrathsfarm
You say the purple band is not as wide, do you mean overall or at a single point. Marans should still have good width at the shoulders, but this should be maintained down the entire back towards the tail. That is Kong’s big issue: his width is lost in the rear.
I’m struggling to tell in the photos, but is the purple band good and rectangular from above? The double purple is slightly triangular from above, I think this is what you were trying to highlight.
Double purple also looks rather triangular from the side: his breast is very lean. Hopefully he is yet to fatten up nicely. This might be true of both and I can only see in the pictures of double purple.
I stress choosing type when replacing your cocks. I think you’ll find that when you breed these boys from under coloured dams back to under coloured hens next season, then you will see real improvement in chest copper.
The narrowness of the hips is the main issue, so choose the one which is most rectangular from above (provided it has no other major faults).