Go to the library. Look at a couple/few issues of HGTV Magazine. They have a monthly feature of exterior color combinations.haha. That's not bars on the door, that's a storm door. Crime is low on this street, thank goodness.
I like the Navy or Charcoal idea.
My initial thoughts were to paint the door and the trim over the porch the same color (just what color)? and the window and corner trim bright white like the columns. I know that it's not necessary as it's a rental. This happens to be the ugly house on the street, I would like to make it at least fit in.