It is interesting to me that we "only" have 19 pages of comments. I think it is because it is such a puzzle. The ACARS data gives enough information to keep people focused on trying to explain those messages. Without those, the speculation is all over the place.
Would it be possible to reverse the thought process and speculate as to what messages may be transmitted via ACARS based on some of the theories presented? I don't have the knowledge to do this, but a bus pilot would.
For example, what ACARS messages would you expect to see if there was an explosive decompression? If a message indicating a drop in cabin altitude would be expected but not received, it would be less likely to be the initial cause (and within 3 minutes would you expect that such a message should have been generated?).
What messages would you expect to see if a fire started in avionics? Etc. Just looking for other opportunities to extrapolate upon what we know.