I know you're probably going to be sick of all black chicks if you keep a black rooster. Lol. Add some more blue hens to your flock if possible, the blue cochin mix would be interesting. The second generation of your chicks will be beautiful.Those combs look like Blue's comb. Purple and En Croute both have combs twice that size.
Since my intentionally-ordered straight-runs were delayed until fall I was hoping for a "oops" cockerel. I was hoping that Marans Purple would be it because that's the one we called "Big Spot" as a young chick and Marans are supposed to be difficult to vent sex. I hadn't really thought about what having a Langshan rooster would be like in terms of my flock's future genetics.
I do love the sheen of my black hens.. they show green, blue, purple, and turquoise in the light.
My only experience, with langshan males, has been with easter egger/ langshan mixed cockrels. They were very calm, got along well with each other, and were TALL. Of course, their father was/is my blue easter egger, and he is huge (he is part blue orp) so I expected large males, 1/2 (2 of 4) have been blue, also.
I had an easy time rehoming all of my langshan mixed males because they were so big, pretty, and friendly. I stay in touch with the owners and all are happy with them. They are from 1 year to 2 years now.
I have only 1 hen from my older langshan. She is a cuckoo marans mix. She is beautiful, solid black, and lays the prettiest egg- a large, medium brown color, with dark spots. Her disposition is excellent.