Only one way to beat each level...?
Either I was missing some core component of the game, or it seemed like there was only ever one specific configuration that could be used to pass each level. The game looked like it promised plenty of fun, but restarting over and over until you found that one specific placement and building combination completely threw the fun out of the game, leaving it as some odd kind of trial-and-error simulation rather than a game.
Once again, the premise of the game and the graphics are not at fault in any way, it's just the difficulty. If there was some sort of difficulty setting, perhaps lowering the money needed to complete each level, or even just as simple as making shops and upgrades cheaper, the game could be much more enjoyable, and people would perhaps play past level 3.