Why, in nature, is the male-female ratio nearly always one to one? If wombs are costly while sperm is cheap, why are there so many sperm producers?

It is a matter of biological economics. If a species produces fewer females than males, daughters will be more fruitful than sons. Any variant individual who picks up the trait of having more female offspring will have advantages, and will spread the mutant trait through the gene pool until the ratio evens out again.

The same logic will hold in reverse, if we planners try to simply program-in a birth ratio sparse in males. Early generations would reap the benefits of peace and serenity, but selection forces will reward son-production, favoring its occurrence with rising frequency, eventually annulling the program and landing us right back where we started. Within mere centuries, this planet will be like any other, aswarm with men and their accompanying noise and strife.

There is a way to free our descendants from this bio-economic cul-de-sac. Give them the option of self-cloning. Reproductive success will then reward women who manage to have offspring both sexually and especially non-sexually. In time, a desire to have like-self daughters will saturate the gene pool. It will be stable and self-reinforcing.

The option of stimulated self-cloning lets us at last design a world with the problem of too many males permanently solved.