Human breeding programs

I'm reading the book "The Science of Dune" right now.  It's a very intriguing collection of essays from scientists of many backgrounds which discuss certain aspects of the Dune saga as they are related to modern science and possible future science.  I've read so far about the possibility for synthetic eyes, about the use of hallucinogenic drugs and if we'll ever have a hallucinogen which also extends life, about the possible biology of the sandworms of Dune, and about the actual physics of the dunes of Arrakis.

The most recent essay I've read was from Carol Hart, Ph.D., concerning the human breeding programs of the Bene Gesserit in the Dune universe.  This society of women with prescience were conducting a 90 generations long breeding program to produce the universe's sueper being, the Kwisatz Haderach.  Of course, for those who've read the book know, the super being Maud'Dib came a generation early and had the unforeseen side-effect of being independent and uncontrollable by the Bene Gesserit sisterhood.

The author of this article does a fantastic, if brief, job of highlighting the fact that we humans have spent the better part of the past 15,000 or more years domesticating wolves to make our household dog, and now we breed dogs for all kinds of traits (some of which, like in the case of the smash face pugs, is really bad for the animal but makes people think it looks cute).  However, we have not been as careful in our own breeding.  Many people will have children regardless of their own genetic pitfalls.  It makes me wonder, if at some point in the future we will need to start directing human breeding so that our species can continue to evolve.  What if we seek to colonize Mars or travel beyond our solar system.  Might it be better for us to selectively breed the type of people who will be biologically optimized for the psychological stress of space travel, or for stronger defense against radiation damage, or even for the ability to breathe less oxygen and still perform well?  This question definitely jumps deep into the realm of bioethics.  Any thoughts?