Eevee
One of the concepts of Pokemon is they are "pets" that you collect and care for (and then force to fight each other, go figure). But in my opinion there's actually only a handful that I think I'd enjoy having around. Pets give us companionship and unconditional love, at least that's the point I think. I wouldn't mind having a Pikachu around, they're pretty cool. And my personal favorite is Cubone, I have no idea why. And Eevee, brilliantly built by reticence here, seems like a pleasure to have around. But can you imagine a Mr. Mime hopping on the bed with you to watch TV? I'd be creeped out the whole time. And Magicarp is useless, your argument is invalid.
Original author: Tommy