The pro and premium version allow for map images to be generated up to 5400×3600 and 10800×7200 pixels respectively (  Unfortunately this does not always allow for all the pins be be printed at the desired zoom level (or map detail).

There is a trade off between the map details and the visible area that can be seen on the map (this trade off is visible in the web browser as well by zooming in/out), so it’s not always possible that the trade off works with the limited image that can be generated.  Generally zooming in an extra level or two will help to add more detail (and cause pins to appear farther apart).

A basic example of what would happen if someone wanted street level details of the United States (2,680 miles wide) at street level detail (using 264 feet per block and 20 pixels per block) would result in an image over 1 million pixels wide, which would be over 295 feet wide for a printed image at 300 dpi.    The reality is about 1% of the width of the USA can be printed for street level details, likely 1-2% of the height as well.  To get the whole USA in street level detail could require somewhere near 10K images at 10800×7200 pixels.