I know I'm in the minority on this, but I hope the extended cut of the movie throws in some more character moments and slows down the pace a little in its second act. I actually didn't mind the hour-plus build-up to all the action. However, some very interesting character arcs began on the sea voyage that were never really resolved to my satisfaction. For example, Jimmy's backstory: does he have a connection to the island? The Jimmy/Hayes relationship, with Joseph Conrad in a supporting role: is there any more meaning to it? Once the second act got rolling, it seemed that all these interesting character arcs which were only hinted at were tossed aside to make room for what the audience (ostensibly) paid to see: Kong and lots of visual effects sequences.
More action scenes are fine. But I think they (and the movie) would flow a bit better in the second act with some dramatic padding in between. If such moments aren't forthcoming, however, I say trim the sea voyage by a few minutes to remove the dangling story threads. Knowing Jackson, however, I don't think that will happen.
But I will most likely pick up this edition regardless. I'm glad Universal let Jackson go through with this release.