On pokemon emerald which one is better?

Gardevoir because it has a high speed, sp. att, and sp. def. trust me it the best. But it can learn Ghost, physic, electric, some fire, and some bug type moves. With these stats almost no can touch you. With the moveset; calm mind(increase sp. att and sp. def), thunderbolt(relies on Calm mind), physic( relies on Calm mind), and shadow ball(easy defeat for physic pokemon).