What are the hardest traits to breed for?  Is there an order by rank of difficulty in breeding for that trait?  In other words, should I focus on if the bird is docile or look for the coloring (as an example)?

Also, I know that there are some learned behaviors, like egg eating, and there are some traits that need to be bred for, like man fighters.  Is there a list of those learned behaviors, so I don’t need to really worry about that for breeding?