This is a sweet story and soundtrack. I think you've really nailed the kind of pure innocent joy that you get from playing with a cat. I think you could make this project better if you leaned into the nostalgic/sad mood you were shooting for, you could try experimenting with suspended chords, or a section in a minor key maybe could add to that feeling. Regardless, your project was very pleasant to listen to and I enjoyed the accompanying story you wrote for it!