I have an opinion about polygyny--I don't think it's an evil monster, but I do think everyone should be responsible about it. Those who aren't give other Muslims a bad name, but worse, fling themselves against the boundaries of Islamic law, possibly infringing on the rights of others.
I have a problem with the sort of man who would pursue a woman to be his second wife, and devote to her alone all his free time. As if, because the woman is not his wife, he isn't responsible for being fair with his time! The horrible injustice of this to the first wife pains me. Imagine the scenario--after weeks of intense courtship, during which the prospective couple has spent just nearly all their evenings (after work until midnight and beyond) and weekends together, they spontaneously wed without any prior announcement to the community.
The wife, aware that her husband is seeking another wife despite her own objections, is forced to endure weeks of neglect while her husband doesn't feel the need to be fair to her because the other woman isn't his wife. He somehow thinks he won't be accountable for how he spends his time. I have a problem with the man, and I think I even have a problem with the other woman who approves of that behavior. Undoubtedly her heart and hormones are steering her off the proper course, but she should consider the position she is leaving the wife, as she alone monopolizes his time.
So I don't have a problem with polygyny per se, but the abuse of it by some men. I truly love how women are honored and respected in Islam--guaranteed rights often abused by various societies. Unfortunately, there are in fact people in this world, Muslims, who deem important only their own rights, the obligations of women, while remaining silent and ignorant on the rights of women! Many of them will, for example, strongly advocate the right of men to take a second wife, without a word on their capability of treating them fairly. They proclaim the right of men to know where their wife is, and that she not speak to other men, but freely engage in flirtation and romance with women to whom they are not married. They describe their own jealousy as admirable, and their anger as acceptable--but for a woman to respond to her own jealousy or anger, is deemed intolerable! What hypocrisy is this?
Islam is not a religion in which we can pick and choose what we like and dislike. Allah SWT says what can be translated as, "It is not for a believing man or a believing woman, when Allāh and His Messenger have decided a matter, that they should [thereafter] have any choice about their affair. And whoever disobeys Allāh and His Messenger has certainly strayed into clear error." (33:36)
We cannot claim our rights while disowning our responsibilities--that is the nature of oppression, and tyranny. The Prophet Muhammad (saaws) reminded his Companions to "Fear Allah concerning women! Verily you have taken them on the security of Allah, and intercourse with them has been made lawful unto you by words of Allah." (Muslim) That hadith goes on to list the rights of the wife, and of the husband. Allah (SWT) says what can be translated as "And women shall have rights similar to the rights against them, according to what is equitable." (2:228) This is Islam, a religion with guidance and wisdom from our Lord. It is imperative that we heed His words, and those of His Messenger, and not strip our brothers and sisters of their rights, which are from Allah.
For my part, I hope that men who do pick what they want, especially in marriage rights, don't make up a majority--for sure, there are not many such among my acquaintance, and I prefer to believe (in absence of proof to the contrary) that these are the exception rather than the rule.