Good but way too hard
Easy was pretty hard, it is hard to get established, you start out and bam your ass is getting kicked. You should add some units to the easy mode, like on easy you start out with 2 ship (I don't remember what you call them), on medium, and none for hard. Also tone down the amount of enemies for the first 5 levels, and I would love it if you took that smoke cloud hitting thing, make them like bullets instead of grenades. Other than the difficulty I enjoyed the game, but I beg of you, please re-submitt this game and change some of the things I mentioned, if I could get past the 5th level I would play this game a lot.