If you loved The Secret of NIMH, try The Land Before Time
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
What they share
Both films are directed by Don Bluth, and they both carry the tender mood tag, and they sit in Adventure / Animation / Family territory. If that's the register that drew you to The Secret of NIMH, the second film will land in a comparable space — through a different lens.
tender
What The Land Before Time is
Desert landscape, dry riverbed, a lone tree. A young brontosaurus and his new friends, a triceratops, stegosaurus, and others, journey together. Don Bluth's pre-Jurassic Park dinosaurs still hold up for kids on a rainy day.

