The ultimate designer baby is one superior to adults themselves, intended to support adults, not be supported by them. Bringing a new member to human civilization should improve it, not be a burden to it. We don't add a new computer to a network inferior to others, but rather having equal or extra features boosting its performance. Otherwise, we improve the ones we already have, and do without children altogether. Why be fixated on childhood, parenthood, and all things natural, when science allows us to tame nature? It's "knowledge" that has the code of all natural things, that we can only discover and apply, day by day, to nature.
Children will go extinct, eventually. When we have the means to breed humans directly, without passing through the childhood phase, it will be pointless to keep producing humans inferior in size, strength, immunity, intelligence, and maturity, always requiring superior adults to support, teach and protect them.
Childhood is only a phase in life's cycle, like that of a worm or larva in an insect's, whose length varies among species from few days to 20 years old, until a child is able to reproduce. There is no need to spend 15 years or so raising a human, when it can be instantly bred or cloned.
Protecting, raising and teaching a newly born/cloned adult is much easier than teaching present-day children. It will have a fully-grown brain, mature behavior, advanced physical skills, and a vast fast-acquired knowledge, much more than both today's adults and children have.
It can be taught the "basic experiences" of life, through a short preparatory intensive course that includes and outperforms the present decade-long childhood formative stage. Such will be according to the required psychological effect and job it will be assigned to, relieving a child of traditional schooling as well.
At a more advanced state, it can do without such course, and develop knowledge immediately: whether internally, e.g. by constant self-modification, or even gene alternation; or externally, e.g. by data "transfer" from partial/full brain implant/transplant, or attached software. IF brain chips ever become available, learning itself will be pointless, as data will be instantly transferred between brains and machines, or brains and other brains.
The Parenthood Job
Just like childhood, natural parenthood will go obsolete eventually, replaced with professional parenthood. Still, parenthood has always been a profession to some, who, consciously or not, raise children for money, present/future support, legal privileges, etc.; while others find parenthood merely an instinctively-driven, socially-conforming, mentally-obscuring, beneficially-unrewarding, life-consuming burden they can do without.
Parenthood is an investment. By raising a child we invest more or less in a 20-year-old project, if not a life-long one. It requires a sufficient professional knowledge about raising children to reap the aspired profits eventually. Otherwise, being a good parent cannot result from the mere ability to reproduce, the gratification of sexual urges causing child birth, or the love of those sweet little creatures (as we similarly feel toward some animals).
However, because breeding is still a must for survival, the government should regulate it, by forcing or enticing (stick or carrot), e.g. financially, people to have children. More importantly, it should train millions of professional well-paid child-breeders and nannies. Computers and robot-nannies can be greatly helpful, many of which are better equipped and qualified for the job than humans themselves are, to properly watch, protect and teach children.
To move fast and forward, humanity must carry less weight, freeing itself from all "physical, mental, emotional and social" burdens, that childhood is at the top of, having most of the above burdens within. We shouldn't repeat ourselves, history, and natural history, for the sake of mindless attachment:
• Choosing the gender of a child before birth will initially satisfy many gender-obsessed sexists, until they are cured from their obsession after seeing for themselves it makes no difference (just like losing interest in physical beauty when plastic surgeries become common). More importantly, it will create diverse family and society structures (10%, 20%, 50% ... 100% male/female families, groups, societies, etc.); decrease male chauvinism; and help tolerate transgender and unisex humans/jobs/roles.
• We can prenatally avoid many diseases/abnormalities/deficiencies: congenital diseases/disabilities, Down, conjoined twins, etc.; and alter some genes to improve physical and mental skills, thus having "smarter, healthier, stronger, faster, smaller/bigger ... children," according to society's particular needs.
• The age of consent decreases over-time, for voting, driving, sex, testimony, etc. More mature children will do jobs usually done by today's adults: teaching, governing, parenting, etc. Civilization is continuously shortening the young-old gap. However, the child-adult gap will fully disappear when breeding adults directly without the childhood phase.
• The inevitable evolution of boarding schools, orphanages, incubators, and child labs.
Presently, most of the above establishments almost have a social stigma, considered somehow insensitive and inhumane, which is a less scientific than instinct-driven view. Understanding the damage of following our social instinct blindly and attachment to other people, makes the above alternatives to child-raising far more realistic and useful to our evolution.
Their benefits only reflect and embody the benefits of state-sponsored child-raising and child/adult reproduction, compared to traditional family ties that don't differ much from animals'.