should the rio be a boat like the one in vice city and san anrdreas?
Yeah, I remember that boat! But not all the old models from past games return the same way they were before, like the Vortex (from a hovercraft to a sports bike). It might come back at the future with a different name, perhaps.
Also, I've chosen that name as a reference to the base model itself. That Volkswagen is named after Brasília, that is the federal capital of Brazil, and Rio de Janeiro was once the capital of Brazil many, many years ago.