At first I didn't like the level structure, wanting one big sprawling city with no rules. But really I'd be doing the same things, so I got used to it. What if the naming was themed around "North South East West" or districts? "1-1, 2-1" etc just puts me in mind of endless downward dungeons, which doesn't seem to fit with the game's theme to me.
Also, is there currently an end point? I've only made it to 2-2. Big fan if the bomb levels!