Have you considered asking the authors of the typedefs to contribute to that section? My guess they would be pretty honored to be able to help out directly with such a high profile package.

I like types (I've use both Flow and Typescript) in general, but I can also admit that they can cause more type specific coding that is unrelated to the actual problem that I want to solve. It's somewhat of a rabbit hole though, it is hard to go back once you've started. It would therefore be great if there was something more than the test cases provided at flow-typed when trying to to learn redux typing.