Marriage should be strictly a religious bonding. Any contractural agreements attached to a marriage ought to be put in writing, signed by both parties, and adhered to, to the letter. Should divorce occur, the written contract MUST be followed. No more “punish the evil male” divorces as are the case now days.
marriage law/divorce law changes annually.
Your premise utterly fails on the child support front.
In fact your argument falls full square of the lefts/ABA view of children as a mere acessory of sex.
Marriage is not based on popping orgasms.
Marriage is based on propagating society.