A good idea, but it needs a LOT of work. I'd start by even adding just a tutorial level so people know what is happening. Towers only shooting straight forward also makes this game pretty one dimensional, and since they only shoot straight, you need a tower in each block by default. Also, It would be good if you could include in either the "how to play" section of the menu how to build, and what each tower does, rather than just ssying "tower type 'x'". It looks like you have a plan similar to Plants vs. Zombies worked out, and the game looks like it could have some cool potential, but i think it goes beyond just polishing things up here and there. Like, fundamental game mechanics. The art is cool, and the models pretty well done, but I think it would help you immensely if the focus on improvement for your next version is gameplay mechanics, adding info as to what the towers do, and just making the game overallmore user friendly. I'd really like to see what this game can become with more testing, community feedback, and a more finished quality to it, because the potential game i see here is one I think I'd really like to play. If you'd like, if you are intending on improving this game, and adding a lot to it, I noticed some grammatical errors, and if you are serious about turning this game into something that you could really get people hooked on, if you message me all the dialogue and menu stuff as far as words the player sees goes, I'll volunteer some of my time to clean up the grammar and spelling for you