A small number of very intelligent, even genius-level Africans exist. In my time at Harvard and Penn, I have met a handful. Institutions like these tend to concentrate some of the most intelligent people from around the world, so while I understand that the people I met were probably the top .0001% of Africans, they still exist.
If someone were to racemix with one of them, their offspring would have IQs that are well above average.
You can even do the math for Africans:
Avg IQ of Africans is something like 82, but if you account for improper nutrition and healthcare lowering the average IQ, its more like 85.
Assuming that the standard deviation for Africans is 10 points (the std. deviation in the US is 15, but I believe 15 is too high of a standard deviation for Africa due to poverty and poor infrastructure making it difficult for people of high intelligence to find and reproduce with each other).
That would mean that the top .3% of Africa (3 std. deviations above the mean) would have 115 IQ (Avg white IQ in US is 105).
800 million people live in Sub-Saharan African.
.3% of that is 2.5 million people roughly who conceivably have IQs of 115 or higher. Certainly not enough to run a society, but still a substantial number. 5 standard deviations in Africa, or 135 IQ, which is considered especially gifted and only found among 5% of whites, would occur at roughly a rate of 1 in 1.744 million, or roughly 458 individuals in all of Sub-Saharan Africa. It is not a surprise that some of these individuals ended up in top institutions in the world. This is, by the way, calculated at a standard deviation of 10 points for Africa, which is a low-end estimate.
And this is me talking about Africans, the dumbest non-white group in the world, except for maybe Aboriginals, but there are so few of them that no one really cares, and they are so hideous that I cant imagine anyone race mixing with a pure Abo.
With other non-whites, the numbers look far better.
You severely overestimate the unique health issues that mixed-race people incur, especially when you are 5-10% non-white. In the case of Hispanics, most of them are already mixed-race and they have fairly good health when not obese and not mostly Amerindian.
In addition, most of the health issues that occur in mixed-race individuals occur in specifically 50-50 black-white mixes, which are also the most often studied for this type of stuff. Cancer, blood and bone marrow issues are more prevalent among Blacks than any other race.
Your suggestion of eugenics, which is theoretically a good idea, is generally unworkable in a practical context for reasons I have stated earlier in this thread. I encourage you to try to practice it and find your genetically perfect Aryan woman who would also be a great mother and loving wife. I think it is important to set lofty goals for yourself. However, if you don't find her…do you just not reproduce then? Hmm…
Which statement in my post denied that? Maybe you should re-read what I said. Bringing a 140 IQ non-white into a 105 IQ nation increases the average IQ of that nation, regardless of race.