I'm pretty new to the breed myself, actually. I only got my first chicks this week.
I have done a lot of FBCM breeding research though.
So, that being said, are you wanting to know how to breed better quality Marans? Or just things about the breed?
He was most likely excited because you have a different line then he does.
Is he a low-key breeder? (To your knowledge?)
It could be a good fit, just depends on what you think about it, and what you would get in return, (Hatching eggs, a couple pullets, cash, etc) if you want anything in return.
Does your Maran lay pretty dark eggs?
In the U.S.A, yes. They are considered rare according to Google.
They are starting to become a lot less rare though.
I think when the Marans are considered 'rare', is when you find a breeder that has Marans (doesn't matter the color) that are good quality.