[Kednicma]

Race is a little bit the issue, because there's no biological basis for the idea that humans aren't just one single species.

A genuine observation and appreciation of "race" consists of understanding that humans do not have a single appropriate skin tone, mostly. I'm not sure what else there is for you, but it's not there for me.

[Joker_vD]

Yes, humans are one single species, just like the dogs are one single species, and humans do not have a single appropriate skin tone, just like dogs do not have a single appropriate kind of fur, or single appropriate body proportions.

That doesn't change the fact that there are different dog breeds, or different human, well, let's not call them "races" or "breeds", but large vaguely-defined (because they form continuum) groups of distinctly different average appearances.

Edit: just to elaborate slightly, I suspect that if we would undertake a massive gene pool homogenization program (lots and lots of population migrations, cross-whatever marriages and child-bearings), we might in several hundred years arrive at a more or less uniformly skin-toned population in which case one, technically, could term that skin tone as "innately appropriate".

But I personally fail to see any allure in this: what's the point of averaging out the physical differences, they're mostly inconsequential anyway?

[Kednicma]

Gene pools are at least three-dimensional. Just because humans are diverse, does not imply that the gene pool is not well-mixed. And there's a rather famous anthropological observation that skin colors correlate with latitude, as well as well-understood mechanisms which control that correlation; there's a gentle tug-of-war between lowering the chance of rickets and lowering the chance of skin cancer.

Put another way, we already have had centuries of high-speed travel connecting the world and globalizing the population, and we do have region that produce "uniform" skin tones which look like the average of all of the local skin tones, but those regions also have lots of non-"uniform" skin tones. The people that you imagine are but one thin slice of a much thicker and richer gene pool.

Finally, please don't confuse the deliberate fancy breeding of dogs, pigeons, etc. with humans' natural free choice of how to use their sexuality. We frown on eugenics for humans for precisely the same reasons that dog breeders bemoan hip dysplasia.