The picture you paint is a fair and balanced defense of SC's goals based on Christian teachings in their ideal, educated conservative form.
My argument is that although you are correct about the doctrine itself and perhaps even the intent, the practice and/or interpretation comes across in such a manner that it scares average moral Americans (who according to you should have nothing to fear). And, it scares them enough to vote for Democrats. Thus, something must be rotten in Denmark.
I will admit to intentionally nitpicking by pulling out these words you used:
of the ability to control vice
as a prime example of the type of language that SC's use that causes them to split the party. The Vice Police or religious police are exactly the type of institutions that exist in the theocratic systems of Islam.
Moreover, the undoubted response of an SC to the question, "Who decides what is moral?" is to revert to the Christian bible. Unfortunately, there are some disagreements in different cultures with regards to things such as divorce and pre-marital sex. Thus, in a pluralistic culture such as America, talk about controlling vice can quickly be interpreted as an attempt to impose Christian religious values on others regardless of religion.
I do not want you to get me wrong, I agree with most of the basic SC tenets. That is not the point. Rather that their "bible thumping" generally does more damange to Republicans causes on a national (and often state) level than it does good.
If you take a look at the political activism and leanings of the Episcopalean Church, you'll see that on a political level, the differences can run much deeper than that, even within the Christian community.
To this day, most people have "lines" they will not cross. Due to the constant bombardment by the liberal media and academia, that line has regularly been defined downward. In 1900, most people would have been aghast at the thought of permissive divorce laws or form revealing clothing on women. In 1950, these areas would have been more acceptable, but most people would have rejected casual sex and abortion on demand. Tolerance of these areas formerly condemned was widespread in 1980, but most people still regarded homosexuality and transvestism beyond the pale. The barriers against both these areas are falling in public opinion in 2004, but most people would still object to incest, polygamy, and child pornography. If the past is prologue, we may see these perversions accepted as "lifestyle choices" by 2025 or 2030.
Outside of Puritan New England, America never had anything like a religious police. Where personal morality was written into the law, it was the local sheriff or district attorney that enforced such laws, along with numerous other statutes. Laws against vice were enforced as were laws against pollution or disorderly conduct, so that civil order may be maintained. Furthermore, these were local matters. Someone who wanted the "wild" life could find it in the large port cities or the frontier mining towns.
Historically, centralized government has been a far greater foe of liberty than local ones. New York City under Boss Tweed or Louisiana under Huey Long may have been despotic, but no one had to live in either place if he had to. From the 1950s onward, the Supreme Court eviscerated the common law authority of local governments to control vice. Was liberty expanded? Not in the sense the Founding Fathers meant. Did Federal power usurp states' rights? Yes, under the adoption of political theories that have gradually turned our decentralized nation into a centralized one, like those countries in Europe the Founders considered to be poor examples of governance. It may be more difficult for a Huey Long to arise on a state or local level, but centralized government means that America may face a Huey Long writ large. In fact, Bill Clinton was to some extent just that.