Should Having Multiple Spouses Be an Option?

You've hit the nail on the head, @PenguinFoop, the "problems", or dysfunctionality, with marriage, be it polygamy or monogomy, are all about issues with the nature and personality of individuals, not the concept itself.
Your reasons for your own opinion against polygamy is no different than the characteristics of those individuals you state as twisting a monogomous marriage. The only real difference is that more people share yours.