Yeah it seems as if the slingshot is a weaker but faster version of the bow in
SS. I think they could make it deserve its place if it could take out small weak enemies (like the spiders) but not bigger enemies (like bokoblins). Also, it being a slingshot, perhaps you can shoot different kinds of ammo. That would open up a lot of different puzzle and combat potential. Perhaps you could shoot little mini bombs to blow up small things, or shoot something else to distract an enemy.