First, your last point: You are absolutely right that problems are likely to happen one way or another, which is why marriage to non-Muslims is discouraged.
Secondly, you didn’t try to negate the argument put forward by the scholars in cricketplaya’s post: that most societies apply pressure on wives to conform with the husband’s norms. That has been a steady influence for the past millenium and a half.
Thirdly, you argue that the intent of permitting marriage to non-muslims must be to enable men to marry more times. You ignore how Islam encourages a violent response to national violent provocation (rather than turning the other cheek), which means that historically most Islamic states from the time of the Prophet( pbuh) to very recently) were regularly at war. Muslim countries rarely had professional armies and instead used conscripted or volunteer civilian men as soldiers, which means that there were high male mortality rates. Polygamy offered a way of sustaining the Muslim population under these circumstances.
The objective of this third point is that the overwhelming majority of Muslim polygamous marriage have historically been, and continue to be, amongst Muslims. Your point that the purposes of being able to marry non-Muslim women must be to support polygamy is therefore invalid.
So on one hand, Muslims claim that the Quran is Timeless but when arguments arise, you are quick to point out how it’s time bound. Stop comparing the rest of the world with Islam. The rest of the world isn’t claiming to follow Allah, it’s YOU proclaiming how Allah expects us to live our lives.