Heh... Ironically I think Star Trek portrayed the most realistic depiction of super humans. Ever heard of Khan? Genetically bred to be smarter, faster, stronger, and just better than the average human being... However, the same chemicals and attributes that accelerated growth, strength, and intelligence, also accentuated unwanted characteristics: Ambition, pride, cold logic. The more powerful Khan became physically, the less empathy he felt for his fellow man: After all, they were beneath him, intellectually, physically--in every way, [i]beneath[/i] him, like an ant.

The auspicious part is, he didn't hate his fellow superhumans. He cared about them, but that didn't stop infighting from occurring between them, and in the historical depiction of Earth when they took over, their infighting led to the deaths of millions of the non-enhanced.

Increasing our biological capacity, intellectually or physically, also has the repercussion of enhancing the capability to do wrong as well as right. If you increase testosterone to make someone stronger, you also make them more aggressive. If you make someone more intellectually superior without increasing their empathy and sympathy, you make them sociopaths, but if you ramp up their empathy and sympathy, the rest of their emotions will follow as well, leading to extreme bipolar disorder instead.

This is not the kind of thing we squishy primates are really aptly evolved to handle. I'm sure there are good purposes for it, slight enhancements here or there, curing genetic diseases, eradicating vulnerabilities (like the pancreas), curing Alzheimer's , and so on. There are good purposes to this... But to straight up improve the human form in any way that could be construed as a real, serious improvement, you hit Khan. Even then, if we developed a society of minor improvements, muscle stimulus, achieving the perfect height and weight paradigms through genetics, etc, we hit a GATTACA future instead.

Oioioi. This whole business is depressing to think about. It's probably best to tackle it with the same kind of extreme care and caution that we do bio weapons... Because in the wrong hands, that's what this is: A Bioweapon.

EDIT

Basically, whether in pill format or genetics, messing with the human body is a very big shadow zone with a lot of potential problems. Leave alone the human brain. An organ we still don't understand all that well.