This is the kernel of the question, isn't it? The major argument I hear from orthodox (Latin Rite) Catholics is that priests "have" to be celibate in order to be "the most" holy. Meanwhile, from Eastern Rite Catholics I hear about the holiness of their priests. From those who've had former Episcopal or Lutheran pastors who became Catholic priests, I hear nothing but stories of holiness as well.
So why the insistence that priests "must" be celibate? I personally think it's because so few American Latin Rite Catholics actually know any Eastern Rite Catholics and their married priests. That's not surprising, since there are very few of them in the US, largely because of an extremely boneheaded action on the part of some US bishops and the Vatican in the late 1920s. Many Eastern Catholics had migrated to the Midwest and the PA area, and worked in the mines. Their priests came over from Eastern Europe, and often were married. The Roman Catholic priests complained to some American bishops, who complained to the Vatican.
What you have to understand here is that the Eastern Catholic priests had *their own* bishops (mostly over in Eastern Europe, to be sure, but they were NOT under the authority of the Roman/Latin bishops, even though *both* were in union w/ the Pope in Rome.) The Latin bishops were trying to enforce a Latin discipline upon priests that were not even under their authority.
Pope Pius XI in the decree "Cum Data Fuerit" in 1929 ruled that the Eastern Rite Catholic bishops could NOT have married men serve as priests. Outrageous! Imagine the hysteria if the Eastern Catholics had been able to convince Rome to *make* the Latin bishops ordain married men. In any event, about 250,000 Eastern Catholics left the Catholic Church and joined the various Orthodox bodies. One can only wonder (given the large families of those days) how many Eastern Catholics there *would* have been in the US had this dreadful event not happened, and what kind of influence they would have had on American Catholic life.
As it stands now, there are relatively few Eastern Catholics in the US, and *ironically,* there are more married Latin Rite priests (former Anglicans and Lutherans) than there are married Eastern Rite priests. Only a few years ago did a Byzantine/Ruthenian bishop in the US ordain a married man, and it made the front page of the NYTimes (from which I remember this story.)