>>53521260...and that's a good thing!
It's the classic weak early game rpg enemy. While other standard archetypes had to be adapted to fit pokemon's unusual urban contemporary setting(ex: magic slime --> pollution sludge, treasure chest mimic --> pokeball mimic), rats are just as fitting in a medieval fantasy setting as they are in the modern world.
Giving rattata a funny moustache or a job wouldn't make it any better and neither would switching it for a racoon or a beaver or a meerkat because none of those embody the idea of small extremely prolific basic critter better than a rat.
