I would first try to get through the storyline as quickly as possible. If I take too long, then I may lose track of the story one way or another, and lose my interest in the game. This had happened to me once before while playing Pokémon Black 2, which is the main reason why I was never able to finish the game completely. When I'm finally done with the story, I would start building a solid team for myself and take my time to explore deep down within all the locations, so that I can be familiarized with them. d: Kalos seems to be quite a big region, so it would take me an extremely long time to fully explore its routes, towns, and cities.