Thanks much guys
@Aquarits : You got it about the cartouches, exactly what I wanted to do with it. Giving the informations without overloading the map. I saw many maps with little cartouches or keys, filled with a lot of informations, and I wanted to do it in a different way : huge cartouches with a lot of spaces for the informations so that you can read it easily while keeping the central map the main focused element.