I think the real reason for the dearth of priestly vocations comes from the clergy and laity's cowardly de-facto surrender to the corrupt Spirit of the Age on the question of contraception. In other words, although the official teaching of the Church against contraception has not changed, and cannot change, on most Catholics' Top 25 Moral Priorities list, it's somewhere between 26 and infinity.
As a result, Catholic childbearing patterns and just like American childbearing patterns in general: 1.7 - 2.0 kids per completed family size.
With only 1.7 - 2.0 kids to provide you with grandchildren, very few Catholic parents are going to encourage their kids to be vowed celibates. And with no parental example of doing even a tiny bit of sexual abstinence (like NFP), kids don't grow up believing that sexual abstinence is possible or plausible for adults.
It's the root of so many problems. And not only for Catholics.
For instance, if you don't expect any heterosexual adults to abstain, ever, how could you demand that homosexuals abstain, ever?
Contraception has changed our expectations of adult behavior; it has deeply weakened any lifetime vocation based on anything other than self-serving and personal satisfaction.
Similarly, Philippe Delhaye wrote: "During the first three or four centuries, no law was promulgated prohibiting clerical marriage. Celibacy was a matter of choice for bishops, priests, and deacons. ... The apostolic constitutions (c. 400) excommunicated a priest or bishop who left his wife 'under pretense of piety' (Sacrorum Conciliorum nova et amplissima collectio 1:51).".
However, the 19th-century Protestant historian Philip Schaff evidences that by the early fourth century priestly celibacy-continence was not a novelty, stating that all marriages contracted by clerics in Holy Orders were declared null and void in 530 by Emperor Justinian I, who also declared the children of such marriages illegitimate. (http://en.wikipedia.org/wiki/Clerical_celibacy)
I'm going to have to disagree with you about contraception being the root of all that is wrong with our current society. I believe contraception and, as a consequence, abortion are symptoms of a morally corrupt society. Sex outside marriage and adultery didn't just begin once contraception and abortion became legal, they had always existed as sins of fallen humanity. Read the Old Testament for plenty of examples of this. Forms of contraception AND abortion, along with child murder after birth, were common ways of dealing with the consequences of illicit sex. The legalizing of the ways to prevent childbirth certainly DID seem to make sexual conduct more widespread and acts once considered shameful and rejected by the moral segment of society have now become commonplace and it's the virgins before marriage that have become the exception instead of the rule. It is the ever-increasing permeation of evil in this world and which will wax worse and worse.
But getting back to the subject of marriage for Catholic priests, perhaps parents would not be disinclined to have sons join the priesthood if they could have marriage and families. I lean towards this helping rather than hurting the church and, as I said, may help to ameliorate the need to accept men who have homosexual tendencies and the subsequent problems they bring to their parishes.