Assuming you had to pick, which would you rather be?
Centaur. Human from the waist up, horse from the waist down.
Satyr. aka a "faun," like Mr. Tumnus from The Lion, the Witch, and the Wardrobe, human from the waist up, but with goat legs.
Mer-Person. Human from the waist up, fish from the waist down. Ariel and her dad. Breathing underwater comes with it, but of course you can't live on land.