Er, why do I get the feeling that an (older) woman's virginity might indicate the presense of some emotional baggage that will take some dealing with? Enforced virginity is about as close to robbing the cradle as you can get. Not saying we should return to the happy times where girls were married off at 12. But, the only thing virginity is advantaging the owner in, after becoming an adult, is freedom from desease, which can be guarded against by many other means (particularly monogamy or being selective). If a father of a house desires that he not have to deal with the consequences of a pregnant daughter (or fathering son), yeah, I can get behind that. But if she gets out and supports herself, there's zero reason for virginity, unless one has a classical "Vestal Virgin" kind of happy, ideal asthetic, which is just dandy.
I think one of the indirect advantages (and who knows, the Society may have actually designed for this) is that the horny, non-comprehensive marriages of young persons, combined with the sanction against divorce, resulted in unhappy, unfulfilling unions that actually produced more stress that could be harnessed and redirected into the preaching work. Imagine, You marry someone you feel is a hot potato, yet they turn out to want quite different things, have quite different habits, have different levels of morals and conscience, and it drives you stark raving mad. Since you can't relate to your spouse on a.. philosophical, personal level (that has nothing to do with the Society), and you aren't permitted to associate with non-witnesses, that leaves either hanging with Witness buddies, or just getting out in service more to get association with other Witnesses. Therefore, it didn't just pay off to make people sexually frustrated, but also emotionally frustrated by being blinded by the sex, first.
For myself, I was married for a year, and it taught me (what I feel) was 20 years worth of lesson. Now I have what I want to call a wonderful relationship, but That is based on the fact that it Isn't set in stone, because both people are not locked in stone, but instead believe in the Principle of staying together, rather that the Law of doing so. (sorry for the soapboxy capitol letters..)