Don't know if the question is still open after one year, but yes the light pollution map is the most useful tool.
A few tricks :
- having a light pollution source on your back (ie to the NW when you are shooting the rising Milky Way to the SE) is less problematic than in front of you, if your target is low in the sky,
- the altitude can mitigate a bit of the LP : all things being equal, you get (a bit) less LP if you're higher. Depends much of the dryness and layers of the atmosphere, of course.