Eric,
Nicely done. You may want to touch on dfing and how that has stifled creative thought and the crisis of leadership. As the case with any top-down driven organization, those in the lower rungs may have many ideas that could lead to sucessful changes however these ideas are ignored and those that persist are often threatened with dfing. Dfing and the resulting extreme shunning also keeps marginal JWs from leaving which helps prop up their statistics. The poor treatment of ex members has also contributed to anti-JW websites and literature which has an effect on recruiting in developed countries.
It's interesting because I think some of these issues are similar to what the LDS faced. They took a different route by encouraging education, making their preaching (which is still one of the identifying brand marks of the LDS) something that is done for a limited duration for members, and engaging in lots of charitable activities. They are doing well financially, have strong retention rates and IMO most importantly for a religion, still keep a very high level of control on their members. They have kept almost all of their wacky doctrine and are not considered a mainstream religion especially by the majority of Christians.
Your thoughts on preaching and publishing are spot on. I had a visit from a couple of Mormons not long ago and I didn't realize they don't actually carry the BOM door to door anymore. They handed out a tract with an 800 number and e-mail address (I think, can't remember for sure on that piece) that you could contact if you wanted a copy. I bet that they have figured out that its much cheaper to mail out the books that publish a bunch that may end up sitting in some missionary's closet unused.
Overall, I agree with your conculsion that they will be around for a long time absent any black swan sort of event. They are just too big and too wealthy (look at all that NYC real estate they still own) to collapse anytime soon.