I can't speak from experience as I have so very little . However I can read and know you are wanting a brown egg laying purebred , ruling out many of the types others are suggesting . If you want a breed that is likely to brood its own eggs rather than have to incubate them , thats going to narrow the field also . If you're happy with your current orps , I'd get some more if I was in a hurry to increase my flock ; or breed the ones I have if I wanted to rebound more slowly .