Genetically modifying embryos to have certain desired traits is far from being done. The ability to select different traits is much more difficult than targeting genetic diseases. This is because genetic diseases can be caused by a single mutation, while selecting certain traits is influenced by multiple genes. Shai Carmi said how it is much more accepted to alter a baby if it is for a disease versus an outward identity. Also traits can be very unpredictable, even if altered.
In my opinion, I do not think genetically modifying embryos should be allowed with the purpose of a "designer baby." I think it is acceptable to modify in the interest of the health and well being of a child, but to completely change their characteristics should not be okay. If somebody wants to change the way they are, it should be decided by them, not their parents. Also all life should be accepted the way it is, parents should be happy with the way their baby looks without genetically modifying them. I hope this is never something that is available to the public when it does become successful.