The answer to your last question is a very complex one and basically boils down to how one defines an EE (some BYC members have vigorously debated this question). After all, EEs are hybrids to begin with and not actual breeds. Everyone agrees that if you cross an Araucana or an Ameraucana (both blue egg layers) with another breed, you get an EE. It's the next cross that is debated. I personally would not define a 2nd generation EE cross as an EE, but rather as a mixed breed that might lay colored eggs. I think the more important issue here is, will EEs bred to other EEs or to your other list of breeds lay colored (other than brown eggs)? The answer depends on which gene the EE parent gives in the cross. The EE has two genes, a blue one which it received from its blue egg laying parent, and a usually a brown one (it could be white depending on the breed used in the cross) which it received from its other parent. When the EE is mated to another breed (such as your Light Brahmas, Speckled Sussux,Black Sexlinks, Polish, New Hampshire Red, Olive Egger, or Barred Rock), if it gives the blue gene to its offspring, then its offspring will lay colored eggs (some shade of green in the case of your brown egg layers and some other pale color in the case of your white egg laying Polish), but if it gives the brown gene to its offpring, then its offspring will just lay brown eggs.
