Background maps come with a transparency option, but that doesn't really render well against linework that you'd normally view against a dark background.
If you attach the Google 2D map layer via the level dialog you can invert the map's colourisation - this works great against linework and a dark background and renders on the screen beautifully, though when you hit Fit View, the view's extents are forced out to the edges of your geographic coordinate system, not just your elements.
So, if the background map had an Invert colours option, the dark background would be nice and clear, and Fit View would still apply to just your elements.