the problem with the eugenic aproch is two fold, there is the whole 'it wrong to dictate who you can and can't have childeren with' argument, wich is mostly ingrained in empathetic emotions, wich is mostly ingrained in instinctive behavior (imho), but perhapse the bigger problem is it is indirct and slow, it would take many many generations to acomplish with eugenics what genetic engeneering could do in a single generation, all that is needed is a firm understanding of what genes do what, natural selection would fill in any gaps we miss no need for an unatural selection process, when we have the ability to rewrite the genome.