It took me a while (about two months, actually) but I finally got the expanded version of Ridley Scott's Kingdom of Heaven watched, as well as the thoroughly confusingly organized set of documentaries that accompany it. (Couldn't they come up with a way you can click on what you've watched). I have, however, given up on ever watching the commentaries, as much as I'd like to.
The verdict from my perspective is that this is a much better film. As much as I liked the original, it was still not that great a film. This film answers several key questions that were left out. For one thing, it explains that the priest that's harassing him at the beginning is his brother - so it makes more sense (although why he's in jail isn't explained). More importantly, it explains that he's an expert in military fortifications, a critical point that is left unexplained in the theatrical version (but it also argues against Orlando Bloom in the role. While I think he does fine, he's not the right guy for this role - maybe you don't need Russell Crowe, but you need someone with some age on him). It also includes "the boy", the young Baldwin that replaces his leper uncle as king of Jerusalem for a short period. I don't disagree with leaving him out of the theatrical release - his story is strictly unnecessary (although historically accurate, sort of) but in this extended version I like having it there - it does add something, and explains Sibylla's downward spiral during the siege a little better. This is the definitive version of the story.
The documentaries - amazingly enough - don't overlap at all with those on the prior DVD set - and the major documentary provides a very good story of how the movie was made and that various issues and concerns and problems as it was being made. To its credit, it accurately records that the movie was a commercial and critical disappointment when it came out, although it reports that the extended version was better received. My problem with the documentaries after that is that you have to excavate in each section of each disc various sub-documentaries, which is not always easy to do. But they are informative.
Bottom line for me is that I'm glad I invested in this second version of the story. It upgrades a movie I already liked from a B to about an A-.