Some dictatorial totalitarian regime?
Let people make their choices when it comes to their genetics once we have the technology to make alterations. Not only is it the ethical decision that respects people as autonomous beings it is also the best way to avoid conflict, just let people do with their genome what they will.
For parents altering children in the womb there will of course have to be some regulations in place, and the regulations should be even more strict once the child is born. But generally adults should have free reign with their own bodies.
The Earth can barely sustain the population at its current overall size. If individual humans suddenly become physically bigger and there is not an equivalent or greater offset in terms of a reduction of the sheer numbers of us, then we'd need too much food, air and water to survive.
While tools and methods presently exist to genetically engineer humans, we must ask ourselves if it is something we wish to happen. Nature and evolution over the years have done a fine job of fine-tuning and refining the human body to best suit its environment on Earth. We do not know what the risks associated with such a genetic experiement would be, and right now is not the time to find out.
I am not against genetically modifying humans to prevent disease and illnesses, but genetically modifying humans to become supersized or superhuman poses ethical issues. Where do we stop? Should we allow parents to be able to pick hair, eye, skin color? Designer babies. Messing around and playing God will have unintended consequences
I do not believe we should genetically modify humans to become super-size. If we were larger we would simply take up more resources, especially food. I think becoming larger would simply enlarge our problems as well. I'm not at all concerned with being big, I don't think there is a problem with our current size.
I do not think we should genetically modify humans to become super-sized. I think that doing such a thing would be unnecessary and dangerous. I also think that it would create an imbalance in society if such an act occured. I think that science should instead focus on finding cures for disease.