I am not getting as much U shape to the back as I want, some of this years hatch are dished a little in the comb.
I found that the u-shaped back took a little while to develop. My younger pullets didn't "stand pretty" until they were 4-5 months old. I think they were too busy running around, avoiding the adults, and getting into mischief to flaunt their stuff.
I don't breed Doms, so what I've got is what I've got. Personality means more, but of course, we all like that pretty Dom silhouette.
We didn't hatch any Doms this year, and last year's girls weren't worth keeping. (Neither in looks nor personality) So, I currently don't have any. Hoping we'll hatch some in 2020.