If the world was now filled with pokemon then I would begin building a team of stronger Poke's but with Pikachu as the lead. It's a rounded Pokemon, very agile, by no means the best but good enough for the one-on-one trainer battles while avoiding causing damage to public property and the local environment. Seriously could you imagine a battle between a max levelled, Salemance and Dragonite? One misplaced hyper beam and that's half the town gone...