Adding functionality to cats as pet

I think it would be great if cats, unlike dogs, weren't given functionality for survival help. Instead, it would be better to give cats aura effects that they emit within a radius of a couple of blocks. For example, a witch's black cat could bring bad luck or poison, a desert biome cat could grant haste, and a white cat could give good luck or villager discounts. Right now, cats don't really do anything except being used in creeper farms.