We humans

Don't painc, its just a curiousity, my question is: If you had the opportunity too add/change/remove something from a person because the specie has to evolute, what thing or things will you change?

That would be a very hard thing to pin down because what is a weakness in one could be a perfect fit in another but essential for both. Evolution happens on such a finite scale it is hard to tell what stays and what goes. The way the world is today and the influence man has made it is nearly impossible to see the changes that are happening the way the Darwin first saw them so many years ago.