Sims will inherit body and facial types, but not details like freckles or teeth, no. They’ll also inherit one of the parents’ skin tone or a mix between the two. They’ll inherit hair and eye color as well, but hair color goes based off of the current hair color of one of the parents. So if both Sims were born blonde and on a whim you changed them both to redheads, the child would inherit the red.
As for what I expect from future versions of The Sims, I can’t really say. I’m not too focused on next iterations, if there will be any.