...This is quite possibly a snapshot of your brain...
I like the linework in the hair. The colors overall are interesting. The tree is really distracting and doesn't fit with the rest (trunk and leaves) and the light post seems like it is in front of the tree. I think it could use some more line work here and there to tie it all together with the people.
I was going to say something about the tree too, but adam beat me to it. the cactus pot feels like it should overlap with the window sill a little. make the tree shape (trunk and leaves) more interesting that i'd call it good.
Dude! I love this! It is so awesome. Very cool. It gives me flashbacks of illustrations from when I was a kid.