This game really isn't that good. Defender and Castle Defender are much better. I suggest fixing a few bugs. Like my -5000 score for one thing. Also, the game is way to easy, especially when you upgrade the archer and mage. I don't even have to play the game. Oh, and if you just hold space and click you can "rage" click whenever.
The new calender "fail-safe" button can easily be abused. Just keep clicking it repeatedly and the enemies will keep looking for a new path and not attack. I suggest making it so you can only click it every 10 seconds or something.