One point I've come across is that, whereas the word "Second" in Daily's book is always pejorative (as it would be to the Greeks, for whom "second" was always a lesser emanation, the finite to the infinite "First"), "Second" in Christianity is above all, coeternal, coequal, and intermediary. Within the Trinity, "Second" is not "secondary" but Central. Woman, more than man, is created in the image and likeness of God particularly in his Trinitarian relationality. Whatever her particular vocation, woman is called first to be the center of God's providential saving work in her own life and the lives of others--her children, in whatever sense they are hers. Man, relative to woman, is 'helper' (as Joseph to Mary; as Peter to the Church), and thus auxiliary and decentered--he is not the terminus a quo of the relation. Yet he is also an image of Christ, image of the Father, thus introducing an inequality which breaks open the relation; allows it to participate in higher orders of being, and also making it fruitful for the growth of the kingdom.
Within the Trinity, that which is Primary, that which is Central, and that which is Ultimate are One but also Three. So also in family and in the feminism question, that which is primary and that which is central are not one and the same person. The truer title of a book revealing God's dealings with woman would be "The Church and the Central Sex".