The EE thing is provoking. Having said that and admitting to being somewhat of a purebred fanatic, I think it good to remember that all these various breeds were developed through selective breeding. They all originate from they wild fowl, with the exception of a couple of the jungle fowls which are pretty much as they came from the jungle.
The Ameraucana is a relatively recently breed, and it in fact was originally developed as a bantam with individuals then using the bantams to breed up large fowl.
As a newer breed there are still some variances in the genetics from strain to strain. I know very good breeders that have lines which produce white eggs, which they use in cross breeding to their other strains for various reasons.
The blue egg color seems to be the magnetic attraction for many. If they can cross to anything and get a female that lays some shade of blue, green or whatever they are happy.
The fact that the bird lays an egg other than white or some shade of brown is enough to qualify it as an Americana (not Ameraucana) to them and that is superior to an EE?
I am nearly there in my project using crosses of Marans and Ameraucanas to reliably produce pullets that lay an egg the color of purple velvet. Stay tuned for further updates.