If you loved One Piece Film Red, try One Piece: Defeat the Pirate Ganzack!
A bridge between a film you've already seen and one most people haven't. One Piece: Defeat the Pirate Ganzack! has roughly 18.1× fewer votes than One Piece Film Red — it's a deeper cut, not a mainstream recommendation. 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 Goro Taniguchi, and they both carry the playful mood tag, and they sit in Action / Adventure / Animation / Fantasy territory. If that's the register that drew you to One Piece Film Red, the second film will land in a comparable space — through a different lens.
What One Piece: Defeat the Pirate Ganzack! is
Here's an anime short that's not short on exclamation points. Luffy and Zoro land on an island and team up with a local girl to rescue Nami and other villagers from the pirate Ganzack. It's a perfectly serviceable way to spend half an hour.
Ask 
ChatGPT
Claude
Grok
Le Chat
Perplexity
for a deeper bridge
ChatGPTClaudeGrokLe ChatPerplexity