TypeScript's value isn't just in catching bugs — it's in making refactoring and navigation dramatically faster in large codebases.
One underused feature is branded types and nominal typing for domain concepts. This prevents mixing up IDs from different entities even when they are both strings.
I've also become a big fan of using satisfies and type predicates to make runtime validation play nicely with the type system.
The biggest productivity win for me has been investing time in good tsconfig paths and barrel exports. Navigation and imports become frictionless.