This is a creative approach of this prompt. There are many things you could add to make it polished. You could add some background music, animations of throwing the ball and fetching, and just a win scene after fetching the ball. I think the models are all great and the character moves smoothly. Adding some UIs and mechanics will make it more fun. At first, I didn't realize I was supposed to fetch a ball. The ball is too far away so I guess a little introduction would help. Overall, Good job!