It took me a death to realize the colors of the packages and houses matter, but I love this! Very simple but fun. I only got to the second level because of how many zombies there were D: It would be cool to have upgrades, like after eah level you could pick to throw packages farther or carry more type of thing!
I was thinking something along the same line. There are too many zombies by the time you get to fifteen packages, and the lack of ability to improve kind of prevents me from wanting to push further. Also, by level two, every time I get out of my van, I'm attacked by one or two zombies, so I'm practically starting with three out of five health. It's overwhelming.