What are general reasons, other than space, to keep Bantams over Standard sized chickens? Are there advantages to keeping standards? Can you keep both together? I am staring out with a small flock of around 12 chickens (after I sort out the roos). I am attracted to Aracaunas, Silkies, And Cochins. Would the standard Cochins be too large to keep with Bantam silikes, for example? Thank you!