I like how...
...you have something to do as well as build towers. So you can aid in killing them. Makes this tower defense game so much more interesting than others.
Plus the towers were more realistic than others on here.
I think you could add some upgrades to it to make it better, a few more tower styles, maybe make the money limit a bit easier. but the towers that are cheap are easy to kill, that kind of thing
That's why it's an 8 because I think you could still improve this, and I hope you do :)