I love it! Every detail that's been added in I like. The music starts a little bit ominously, but then gets better I think.
You could add in more oppurtunity for strategy by having two seperate health counters, one for paddle durability, and one for ball count. I would try to find some way to expand on this idea without taking away from either of the original games. Potentially, you could mix in a third game. Anything to keep the players engaged. Of course, it's a game jam, so naturally we're all short on time and sleep.
Adding a couple more sounds for winning and losing might also make the game more fun.
Other than the simplicity great game! My favorite take on the theme so far (besides my own)! ;)