I disagree with most of your post, and the part I don't disagree with, is points that you agree with Nihil but neither of you seem to have realised.

Childlessness is actually something to be extolled.

Unless you are pro voluntary extinction, or so misopaedic that you prefer there are no children - which seems to be pj's position along with, say, the children-free hotels and restaurants movement... NO.

Far too many people have children before they're ready to, and both parent and child's life suffers because of it.

But their not being ready comes granted precisely because of the points that Nihil was making... not to mention one that is also implied - unplanned pregnancies due to sexual diseducation due to all of the above...

Only people who are ready to provide for their child's every need should have them.

In principle, yes. In practice, though, nobody is ready to provide for their child's every need, and that is never going to change. I agree though that bringing a child to this world is not a matter to be taken lightly...

With a greater ratio of adults to children, children would also receive more attention too.

Prove it: use the former East Germany and almost any African country as cases.

One might look on not having a child as denying a potential life, but taken to it's fullest extent, that concept simply fails.

I agree - lives (and therefore rights of the living) are not such until they are created, unless of course you argue that every egg and every sperm has a right to be used for breeding - which I don't...

Every adult female can have a child once a year. Assuming 15 fertile years (more, but take into account deaths) you could multiply the population of the earth by more than 7 times in a single generation, if we simply bred non stop.

Not necessarily - not if we constantly flatten the upper part of the demographic pyramid.

Unacceptable.

Unlike your previous sentence, which pointed to the positive, "Unacceptable" implies a normative argument.

So, why do you consider unacceptable to multiply by 7 the human population of the earth???

You didn't say it was impractical - you said unacceptable, and I am therefore asking for an ethical / moral / philosophical argument why that is so...

Many people don't control their breeding.

Agreed. Nihil implies this point himself, with his criticism of parents.

Those who do not breed do so in lieu of caring for the children who exist (despite their irresponsible parents) by not further burdening the earth and overincreasing the population. This is to avoid the starvation of the species and suffering that incurs with overpopulation competitions.

Overpopulation is a myth - we can easily feed 2 or 3 times the human population we have now. And that doesn't even take into account the constant advances being made in improving the production and quality of food. It's not unthinkable that we would have the capacity to feed 7 times our current population by the mid 21st century...

The sad thing is, this leads to evolution which favours genetic tendencies for irresponsible sexual behaviour.

You fail to realise that "irresponsible sexual behavior" and "overpopulation" were themselves how humankind could make it through the natural disasters that seem to have taken place during its history as a species... Those who were "not further burdening the earth and overincreasing the population" did not contribute much to survive the ice ages and volcanic cataclisms of the last few hundreds of thousands of years...

All we can do is attempt to control this somewhat through spreading memes. The virtues of not having children is one of them.

Instead of memes about good raising children, like Nihil argues?? Are you sure you are not arguing for voluntary extinction???

If people choose not to have a child simply due to selfishness, fine, good, because anyone so readily swayed shouldn't have one anyway. Most people have them due to selfish irresponsibility and lack of foresight anyway.

Agreed - and Nihil says that too. That is why he regards current parenting as somehow ill...

Another thing that should be stopped is valuing women only as breeders,

I don't think women are only valued as breeders in the same societies where the problems Nihil mentioned exist. He explicitly said that Today, children are a burden [...] It is no longer "fashionable" to be a parent. - so no, women are not valued as breeders, period... not where Nihil is talking about anyway...

and valuing a life only by the passing of one's genes and raising of one's genetic family.

Implied by the above.

This is a horrible thing. The reason is, that these ideas are passed on to the children. Choosing to demean your life to breeding (and this is different than caring for children, which can be done through adoption, teaching, volunteering, etc.) is your personal choice, but by passing that value system onto a child, you greatly limit their potential for personal development and personal value, and contribute further to overpopulation.

Again, your argument is only valid if you are defending voluntary extinction - because you seem not to realise that breeding does not equal bad / irresponsible parenting...