The idea is original, but to be honest, I can't really see this going anywhere. These kind of games are fun when you have to kill time while something is loading, ironically, you can't play the game while it is loading, even though that takes a massive amount of time.
One of the things I dislike the most is how slow-paced it is. Try to speed stuff up, make the waves faster and shorter, to have the difficulty increase earlier. It took me over 5 minutes to get through the first wave only, which just takes too long.
Furthermore, I think it's kinda unfair to have you combo-meter to stop at ×8. While we're at it, the '×' looks really off and could use some work, in my opinion. Overall, the game is kinda original, but not really that much fun, it'd be cooler if made everything go faster, although I don't think it will make the game much better as the over-all concept just needs a lot of work.