"...eugenics. This is not something I am opposed to from a scientific point of view. We do it with livestock, so why not us?"
You can be predisposed to a lot of things -- diabetes, heart problems, and so on -- most of those don't necessarily prevent you from reproducing. But being "intelligent, motivated, imaginative" has little to do with having a "disadvantageous" genetic makeup leading to health issues. So you are not taking the whole "nature" part into account, only part of it.
Also note that I am not necessarily supporting eugenics, just thinking aloud. At the same time, I don't see how your proposal is any better than "classical" eugenics from the human rights point of view. We can take it one step further and assign an importance coefficient for voting. Let the professor/researcher vote count for 3 units; as for the proles, .7 will suffice. After all, why shouldn't people with intelligence, self-control, and imagination have more of a say in where the country is headed -- it's mostly their kids who will live in this country in the future, so it's only fair.