Orpingtons are better for meat, but not great. If I were to try this, I think that I'd have barred rock hens, cochin hens, and barred rock roosters. BRs lay very well and get pretty heavy, and cochins are great mothers.
For the feed- feed everyone all flock and offer oyster shell on the side for the hens. Chickens that go broody often are silkies, cochins (especially bantam cochins), salmon faverolles, and orpingtons.