>>107040549On a purely visual level, 1>3=4>2. Storywise, 2>1>3=4.
The first had great drawings and special effects, and that's really all I watch Don Bluth films for. The story is the usual Bluth stream of consciousness, poorly timed and unpolished dialogue set to intrusive music, but it's not as bad as his later stuff.
2 had a good backdrop and character arcs, but it was wildly inconsistent visually, with wasteful animation on bad drawings. The difference in the quality of work between the A/B/C teams was jarring. It's the same problem with We're Back A Dinosaurs Story.
The direct-to-video sequels had the efficient animation and solid drawing of Japanese-made cartoons I happen to love, but they weren't flashy and the stories were deathly boring. I believe the second movie was retconned and these moved the story back to New York, which was a mistake. The frontier was far more interesting.