Author really doesn't make an argument. Just assumes things need to change. Without demonstrating they actually know what are the duties of a man and a woman. A woman in a marriage can have the extra money and choose what she wants to do with it. A man's wealth is supposed to be used for providing for his wife and children. Mother, sisters, grandmother etc and anyone else in the family. So to make this task more difficult by chaging the inheritance laws is not logical.
About polygamy. The author seems to think everyone is wealthy. Right now in Syria there are many Iraqi refugess who have children and must prostitute themselves to survive. So which is better polygamy or prostitution? I'm sure there are women in singapore in the same situation. There are even women in far wealthier nations in a similar position.
And a wali is absolutely needed in this day and age. With divorce rates well above 50% in North America having a rational observer/negotiator on sidelines is never a bad thing. Even muslims are following this trend and are divorcing more. This causes extra stress on society and for the family unit, so maintianing divorce laws which limit the chance of divorce are also neccesary.
Of all the things Allah allowed divorce is the most hated.
And I wonder what inadequete maintaince means. Didn't get enough gifts? Or living in desperate situations?