If you look at the OP, the OT is cited as providing insight into what God's plan for marriage is.
No it isn't. Maybe it's you that should be looking at the OP. However, the OT is a source of reference for gender roles. It can't be overstated that women were not in charge by God's design. The Aaronic priesthood was all men. The leaders, judges, and kings too were men, and when Jesus arrived and began his ministry, he chose all men. I've heard feminists repeatedly refer to a "male God" who institutes male dominated society for the subjugation of women. It's one of the many ways feminism is not compatible with Christianity, for they twist it into something that it's not, as evidenced by your posts. Men are created for leadership, especially in regards to religion. Women have very different, very unique, and very invaluable roles that are DIFFERENT then men's. It's the feminist lie that says because a woman can't do everything a man does, she's being oppressed. Stop listening to these lies from Satan.
I see that as more of an economic issue than a gender one.
That's nonsense. It's about lifestyle more than it is about economics. It's about people who enter into a marriage and then ultimately a family who have not learned to sacrifice for something greater than themselves. They continue to live immature, self focused lives and they want things, a bigger house, a newer car, and fancy clothes. They claim to "need" two incomes when the truth is they refuse to live on one and make it work. Families are very resourceful and, leading by example, my family does just fine on my modest salary as a truck driver. So yes, it can be done. The continued pursuit of self in a marriage and family ultimately exacts a toll on children, for they are made to pay the price because mommy and daddy want things more than they want a close relationship to them.
The command to take the virgin women as spoils of war was a direct command from God. The 10th commandment puts a man's wife in the same category as his other possessions.
The demonic philosophies of feminism have warped your mind so that you see oppression wherever you look. It's no different than those who see racial oppression everywhere and blame white domination for their own failures. Protestants have categorized the 9th and 10th together whereas Catholics have, appropriately separated them. Ye shall not covet thy neighbor's wife. That's 9. Then ye shall not covet thy neighbor's possessions. That's 10. So even your viewpoint is based on nothing more than how Protestants have chosen to conflate two very different commandments, lumping women in with oxen.
Not everyone thinks in such black/white terms.
Satan's favorite color is grey.