In places where abortion is legal, the woman can choose to get an abortion without even telling the father. Also, in divorce courts, juries are biased against men, even if the mother is abusive and the father earns more money. Basically men have no reproductive rights. So if yet another right is taken away from men, then they should be given one in return. Another thing is that women can rape men and still sue them for child support. https://en.wikipedia.org/wiki/Hermesmann_v._Seyer
They can also sue sperm donors for child support. Reproductive rights should be given back to men, so if the man does not get a say in whether the baby is born or not, he should also have a say in whether to help raise it or not.
Ability to pay with proof the person is trying to get a job, should be considered. Whether or not the man was actually the biological father should also be considered. And if the man takes custody the woman should be equally liable for child support.
In cases where there is no other parent who has money to help raise the child the government should pitch in and pay the child support. Children shouldn't get special privileges just because they happen to have an absent parent that can afford to pay child support.
In cases of ordering payment of back child support where the child is now an adult all the money should go to the now-adult child, not either of the now-adult child's parents.