Eliminating poverty is the best and probably only socially acceptable way of 'improving' humans (and even that will face friction with some groups). I think we already know enough to say that in a world without poverty, a huge chunk of what we consider negative traits will atrophy over a few generations. We can tackle the rest, and work out what that means, if we get that far.
I talked to a friend who is a doctor once, and he started telling me some of the ethical concerns about studies. At some point my mind was reeling from all the implications and I don't know how they do studies in the first place.
I'm sure there are common treatments in use for hundreds of years, but if they were discovered today would never get through the approval process.
