Castle's earlier nonsense about a Utopia is rather laughable, and also scary. Your premise is easily defeated: First and most importantly, "desirable" traits are arbitrary and subjective. You wouldn't be selecting the best traits, you'd be selecting what only you believe to be the best traits. It wouldn't be an improvement, it would just be a change. Second, diseases mutate. Selecting for stronger immune systems would just speed up bacterial and viral natural selection, making them stronger. The likeliest outcome of such an attempt would be to inadvertently create a super-virus that decimates the world's population. Third, working toward an appearance standardization would likely result in more of the mutations you're trying to avoid. The more removed people are genetically, the less likely they are to share recessive mutations. You'd compound the problem, and create a metaphoric cultural incest. Fourth, achievement is not always genetic. You might have some success in athletics, but mixed-to-no success in acedamia or general "life success" (also arbitrarily judged, btw).
You also talk about making it "as nature intended." Nature's a f*cking b*tch. We're MUCH better off now than we were when natural selection meant more to the human race. If you want to strip us of civilization and return to a barbaric pursuit of genetic improvement, well, that's pretty messed up.
Finally, your way of running such a utopia would strip people of freedom. You would be dictating how people lived, an offense justified by no end. Your ideals would fail, you'd be killed, and the world would be better for it. F*** that utopia. Sounds more like hell to me. The funny part is how delusional you are, and the scary part is that you aren't the only person whose idea of a perfect world is so f****d up.