On the other hand, I usually stop and inspect myself whenever my reasoning that something is bad is not because it hurts me, but because I can't accept to see others improve.

Good point. Not many are as clear thinking as you. The one point against this kind of manipulation is that I'm not sure we can predict all the potential consequences. By altering the genes of a few individuals we may incur unintended consequences in generations to come. So whilst we may not personally suffer from the guy next door giving siring to "superior" children there may be trouble a few generations down the line. Perhaps I'm overly pessimistic...