Whelp, I'm only on Gen 3 of my ID but thus far, founder's bright blue eyes are sticking around. Gen 2 is nearly identical to the founder while gen 3 has lost most of the interesting facial traits. At least we regained the founding spouse's blue hair so that counts for something. Beyond that, a helper's family is on gen 3 as well and so far the faces are pretty close to identical, especially the noses.