Australorps, Orpingtons, Cochins, Brahmas, Silkies, Sussex, and Faverolles all have a well deserved reputation for being friendly, calm, and gentle birds. Of these, Australorps are the best layers and Silkies and Cochins are the poorest layers (although they are the best brooders and mothers). The lay rate of Orpingtons, Brahmas, Sussex, and Faverolles is about the same, although Brahmas eggs can tend to run a little smaller than the others. Silkies, being bantams of course, have quite small eggs. I don't know if any chickens eat fleas. In 50 years of raising chickens (dozens of breeds), I've never personally observed them eating fleas. Whatever breeds you decide to get, good luck with your flock.