(Apologies in advance for this long post!)
True, you and DNCall have an interesting suggestion there. I definitely think that Rutherford created an environment of separatism, that is, he wanted to remove the religion as much as possible from mainstream Christianity. I don't know what his motivation was, but he was the one, I believe, who coined the term "religion is a snare and a racket", thus making it clear that the JWs were not a mere "religion", simply "the truth".
Every orthodox term in the book was rejected from the JW vocabulary, to the point that Witnesses to this day refuse to let themselves be described by any typical labels besides "Christian", no matter how accurate they are. "Millennialist", "fundamentalist", and "creationist" are all accurate but the average JW would deny that they apply, out of a kneejerk reaction, because they like to imagine that they're special, one of a kind. A label, after all, is something that would allow them to be lumped in with other religions.
In addition to the points you mentioned, Socrateswannabe, Rutherford also went out of his way to attack the Catholics and draw their ire. While the blood teaching went into effect under Knorr, AFAIK, this was not long after Rutherford's time and I imagine the climate that he had created was still fully in effect at that time. So you might be right that there was a desire there to create the antiestablishment "brand" of the Witnesses.
Was this done insincerely, like an advertising agency would do? I hesitate on this point. I think it was more like going with what worked. People were attracted by the religion's differentness, their unconventional teachings like the paradise earth. Remember, the two-class, great-crowd-on-earth teaching was a defensive maneuver to explain why the JWs were getting uncomfortably close to 144,000 in number. But it worked; people were intrigued by this different way of reading the Bible (that is, cherry-picking the Bible).
As you indicated, Socrates, and in line with my earlier comments about viewing organizations as organisms, we know that life expands and adapts to fill all available niches. The Watchtower's niche was basically "ultimate contrarianism". Do the opposite of what everyone else is doing. I think the Society did this by unleashing Fred Franz, who worked out new directions in theology through his whimsical, arcane Bible interpretations, and they simply trusted that he would lead them in the right direction, the "different" direction.
(Read Terry's last post on this page, with a quote from R. Franz that F. Franz even made Knorr uncomfortable with the way he prioritized his Bible interpretation over things like consistent teaching. Fred Franz was as sincere as they came.)
I guess that, absent any Machiavellian conspiracy theories that can actually be proven true, we could say that this is the closest thing to an answer to cookiemaster's question. The organization's main goal is to keep going -- even though they're largely a stranger in a strange land these days, what with doctrine based on prophecies made in the 1800s, and depending on information control in a world where that control is becoming harder and harder to maintain.
Recently, sometimes I've felt like the GB knows that the contrarian business isn't going to work any longer and they need to come back into the fold of mainstream Christianity. For instance, note the addition of the KJV and other Bibles into the JW Library mobile app. I remember a poster here claiming (though this is very much hearsay) that a GB member once said privately that he wished they could pretty much throw out the WT doctrine and start over because it was so flawed. It could be that they've decided to slowly inch back into a position that is more tenable for the long term by homogenizing gradually, moving further and further from Rutherford's militant antiestablishmentarianism.
The unpleasant alternative is that the GB will feel threatened and move towards an extreme, pushing the Witnesses to seclude themselves further and further. A point in support of this theory is the ominous sentence from a recent WT that has been much repeated here, about following the directions of the slave even if they appear unsound. However, a line like that could be preparation for anything, including an announcement pertaining to cutbacks in "theocratic activities".
No matter how we look at the Society, we should all be able to agree on one thing: the Society is concerned about its future. 100 years have almost passed since Jesus' supposed enthronment, the generation that saw it is dead, and the GB has bought no more than 20 years before the next D-Day with the new overlapping generations doctrine. They've cut down on everything -- meetings, literature, and more. Now they're holding more and more district conventions in assembly halls rather than renting a large facility.
Like a cornered animal, the org. might become more desperate, though I think if they become more extreme they will shed a lot of followers. (Some here have even suggested that they want to shrink the org. to a more manageable size, though I think this is overestimating their intelligence.) Then again, the key to their survival might just be to become blander and more conforming. This would mean dropping the shunning practice, and maybe the blood teaching, and in 20 years, probably 1914 too.
As some here have predicted, the Society may become more and more of a shadow of its former self, eventually ending up as a web site run out of Warwick. While it can still keep running on fumes more or less perpetually, membership and growth will never be what it used to be.