Agnostic... to answer your question, how about this: It is a fact of life that men are more involved in wars/crime/migrate away from home seeking a better life etc. In Egypt alone there is a pandemic of unmarried women beyond the age of 35 that has reached astronimical numbers (the last count was 15 million). In Sudan the 35 year civil war has claimed the lives of millions of young men and there is a similar crisis of unmarried women there. These women will not marry or have the pleasure of children and will grow old alone. Is that fair?
Depending on how much society accepts the practice of polygeny, it can heal itself and provide everyone with a family to belong to and a husband/father to love and be happy with.
In Sudan, the president set an example for the population by marrying a second wife to encourage men to do the same and provide for more women and families. It is a real problem in human socities around the world and has to be addressed in a fair and logical way.