Wheaten Marans are my favourite, they dont lay the darkest maran eggs but they do look beautiful. Even then their eggs aren't light, they are still dark.
Exchequer Leghorn egg (white), Ex Battery egg (light brown) and Wheaten Maran egg (dark brown).
I currently own three wheaten marans which I show and have been quite successful, I started off with four hatching eggs from a breeder in February 2018 and on 18th March 2018 four wheaten maran chicks hatched (two girls and two boys). I named the two girls Spice and Clarice and the two boys Sugar and Shelley. Unfortunately, Clarice died when she was only a few days old

. Eventually, Sugar and Shelley started fighting over Spice so in June 2018 Sugar has dispatched. Shelley was kinder and had better features as far as the standards go. Then in April and May last year I hatched three maran eggs. Unfortunately, the first two (born in April) were both boys, I named them Cinnamon and Nutmeg but unfortunately they both ended up being killed because they were fighting and nobody wanted them. The chick I hatched out in May ended up being a girl. I named her Speedy because instead of the usual 18-24 hours it takes from first pip to hatching, it only took her 3 hours! So now I currently own two hens and one cockerel, I am planning on hatching about 20 more this year so that number will grow!
Shelley (2 years old)
Spice (2 years old)
Speedy (1 year old)
So I think that although they don't lay the darkest eggs, in my opinion they are by far the most beautiful in plumage and they are very friendly even the cockerel (most of them time

).