[2021] Maps, which one to play ?

For someone seeking the most “finished” experience, I would definitely point them towards Navezgane. Personally, I love random world generation, because I enjoy exploration and seeing something new that even the developers have never quite seen before. But RWG is still going through major changes, and is thus less finished than Navezgane. You will get more oddities and nonsensical choices in RWG, for that very same reason that a developer has never looked at your particular seed.