Re: back yard EE. I wouldn't hesitate to get my EE from a BY flock IF the rooster and the hen were both EE. Blue is a dominant egg color, so if 2 EE are being bred, the egg color will be what ever the parents carry. The green comes from a brown wash applied to the egg shell as it's traveling through the reproductive system. Debid, I wonder if perhaps you meant that the eggs bred from an EE hen and an other breed of rooster would not produce a blue egg? I'm guessing that that cross would yield more of a darker green/olive color, depending on the egg color of the breed in question. The bigger question regarding bringing in chicks from an other back yard flock is: are you also bringing in disease? NPIP can only test for so much. No matter where your stock comes from, there's always a disease risk. Buyer beware, and take reasonable precautions, but don't let fear keep you from enjoying having a poultry flock.
P.S. I love my EE, and from the reading I've done, feel that they are a better layer than an Ameraucana. The true Araucana is rumpless, and carries a lethal gene, which means that a fairly high percentage of chicks die before hatch. Not a breed I care to deal with!
If you breed Araucanas that don't have tufts you do not have to worry about the lethal gene. The lethal gene is only involved in breeding two tufted birds and hatching their eggs.