Muslims are supposed to get married for the sake of Allah (SWT). If people get married for other reasons then they won't receive it's blessings.
Muslims marry each other to seek Allah's mercy and happiness. It's not about Islamic history, it's about an Islamic obligation to help strenghten your spouse's faith. This is required.
I beg to differ here, we do marry in the way Allah prescribe to us, also it is Sunnah. But we are still marrying for our own sake, and has the right to choose the best possible person suits us.
I agree with you on obligation of help strengthen the spouse's faith. But end of the day everyone is answerable to his/her own deeds to Allah.