My big blue wyandotte is almost always broody -- at least twice a year based on my records. She looks like a big blue poofy beach ball and she's also the dominant hen in our flock. She is a huge eater, but not a frequent layer. Right now she's fostering 2 baby chicks, due to the fact she was going on her 3rd month being broody. I couldn't break her, so I decided to get some chicks and have her move on with her life. And life with chicks couldn't agree with her more; she lifted her wings and adopted them the moment she saw the first fuzzy head!
She is a quiet and easy to handle bird. Haven't had a Cochin, but I think she has nearly the same round shape.