FWIW, I oppose automatically designating the spouse of a pregnant woman as the child's other second legal parent, though if it will be done again, it should be done for both same-sex and opposite-sex couples.
And I would be absolutely delightful to see the current child support laws changed. If conservatives care so much about people breeding out of wedlock, then changing the current child support laws should seem like an extremely high priority for them. But they're not doing anything about this so far, unfortunately.
Child support laws are a lower priority for conservatives for several reasons:
1. We're less likely to be affected by them, as we're less likely to have children out of wedlock, and less likely to divorce.
2. We fundamentally believe a man is responsible for supporting his children, so the basic concept is seen as sound.
3. We're more likely to have the financial wherewithal to fulfill obligations.
None of these mean that the laws aren't a bloody mess, nor that they shouldn't be reformed, just that the problem is less frequently personally experienced by conservatives, and even when it is, how bad it is often is not seen.