This game boasts that it's a unique tower defense game. I'll admit I haven't played many tower defense games, so the uniqueness was lost on me. I'm assuming it was the fact that you actually have a playable character in this game as opposed to being a disembodied tower planting force. Because of this, though, there was definitely a lot more to keep track of in this game than a regular tower defense game, which made the whole deal a lot more hectic. Which I liked, actually. And the story, while simple, was enhanced by the storytelling devices used. The intro scroll with all the people talking on top of each other was fun.
However, I think the game is a little too hard. Ted yells helpful tips at the player while you're playing, which is nice, but it took me several deaths to figure out the cycle of play simply because Ted didn't blurt them out fast enough. Once I did figure it out, I kept dying quickly. Every alien also has way too much health. You have to build multiple towers to kill one. To remedy this, I recommend copying other tower defense games. Send some weaker enemies out first -- ones that go down in one hit from a weak weapon. Then build your way up. Additionally, once the player got hit by a single enemy, it was essentially the end for me because they would all pile up and suck my life away in seconds.
Some sound would have been nice as well.
In conclusion, this game was really interesting and pretty fun when i got the hang of it, but it had a bit too high of an entry wall.