Excellent job! This is loaded with good details, like being able to pet the dog, the screen transitions, the faux-Z-axis that lobbed mailboxes use, and the conveyor belts. Using the dog as a weapon by marking enemies is very unique and intuitive! The enemy attack patterns are also cool, the boss fight at the end particularly was very dynamic and kept me on my toes.
I also very much appreciate the introduction sequence and the stats page at the end, they really help a lot with giving the game a distinct start and finish, which makes the whole thing feel like a very complete experience.
I think it would be cool if you could bounce the ball once off a wall, to be able to hit enemies from behind corners and to open up interesting options with how you dodge.
I also think that enemies would benefit from being faster and having less health. I played the game on Normal and the challenge level was interesting when many enemies were on screen, but by the time you get to one enemy left, they present very little threat yet still take a while to KO. If enemies were faster with less health, they'd be able to still be a threat even when one is left without making cleanup take too much time.
Other than that I don't really have any other suggestions, this is a very solid game!