What direction or directions we go in is a big question. If we decided we wanted taller humans, we could only allow tall people to have children, and we could either kill off all short people or just not allow them to have kids. We currently consider such things to be very unethical and immoral, and I hope we continue to do so. The best hope for mankind overall is in diversity, not in trying to move in one specific direction.
Insects are arguably one of the most successful types of animals on the planet.
They have become many different species now through diversification. Humans are still all one species and we will probably remain a single species for at least the next 100,000 years or so, but we have diversified in other ways besides genetics, to be very differnt types of people. This is called social evolution. Todays' auto mechanics did not evolve from yestrdays' blacksmiths by genetics. The evolution came through transfer of information not in our genes, but in our books and other teachings.