This is a really cool arcade-style game; I think it captures the feel of an early NES release quite well. I liked the art and music, it functions well, and I had fun playing it. My favorite parts were the frantic moments when lots of mice would show up in quick succession and I'd have to dispatch them quickly and efficiently while refilling on pies to take on the rest of the group. My main wish is that there were more of these moments; as the game goes on, you're still often facing small groups with plenty of time to refill on pies, coupled with breaks in between where there's nothing to do (presumably to let more pies bake?). I'm not sure how the waves right now are generated, but I wonder if having an explicit 'waves' system with separate, numbered waves would help with balancing it so the game gets progressively harder and more tense. Those wave number milestones would also make it feel like you're getting further into the game.
Another thing I noticed is that you can actually juggle mice on the roof of the pie stand (only once, though, I think), and you get points when you do this. I don't know if this is an intended feature or a bug, but I think it's really cool and I wish you could keep doing it (with a slightly wider timing window than it has right now) and get increasing points each time. I think the game could use a mechanic like this that lets skilled players get more points without just surviving longer. I also noticed that mice can still kill you when they're falling off the roof, which doesn't seem right to me.
Finally, the collision between pies and mice is really wide and this sometimes has weird results, like throwing a pie at one mouse and hitting the mouse next to him. This can make it hard to know which mouse is going to get hit.
Overall, very cool entry and I think you guys did a great job.