I just don't know how you can cite the tradition of marriage when it is so varied and sometimes contrary to modern sensibilities.
We're not talking about anthropology, we're talking about history.
And in history, although there are variations you cite, marriage is always between men and women. Men and men are not an option.
Of the list you cited, I can only grant you the issue on polygamy. With that said, you'll notice that in most cultures were polygamy is legal it is not widely practiced. That's because wives (when not treated as property) are expensive. Only the wealthy can afford more than one.
Contracted marriages do not challenge my assertion whatsoever. They strengthen it. While a marriage is between a man and a woman it creates a stable family even if the man and woman are not "in love." Buying brides is but a subset.
So, care to take the challenge and note one tradition that is similar to marriage?
Shalom.