This movie is almost too alternative to be Disney. This is a total steampunk offering, which is true to the spirit of RL Stevenson, if not the literal details of the original book. I also think that attempting to turn the novel now into a children's movie would be a failure - in a culture now immersed in the Pirate's franchise, the classic tale would come off as a poor cousin, with no ghosts or magic to its name.
This is one of the few Disney movies with strong males, in various moral shades from the youthful, rebellious hero to the very grey almost-villain. My kids love this movie - all four of them, two girls and two boys. The adventure is far more exciting than most North American animation, and unlike the truly atrocious Atlantis movie, the plot and dialogue are clearly comprehensible, and the characters are engaging.