Alien World Version 01

This is a not yet complete Alien World. There are a bunch of things I want to do concerning more detail on the police building, adding a taxi possibly, adding more residents, etc. I've been working on it off and on for about 3 days and wanted to get some feedback before I went any further! This, like all of my pixel art, is drawn in the standard web color pallette only. I like to confine myself to those rigid controls as it makes me think about placement color and shadow a little bit more.

Thanks.