I'm not sure if I can see Eto paralleling with Ukina and Ken with Yoshimura, or if it's better for the parallels to actually work in reverse in this case (Eto paralleling with Yoshi and Kenny with Ukina).
Yoshimura seemed like a pretty lost individual before meeting Ukina, but Eto is lost by no means imo; she perfectly knows which path she has taken and strives every day for accomplishing her goals. Kaneki, on the other hand, really looks lost and aimless most of the times.
A parallel between Eto and her father could be their common need to be saved. Ukina showed Yoshimura a new way of life and opened up to him possibilities which he didn't even know existed; she redeemed him. I think I can see Kaneki becoming Eto's Ukina in the near future.