I'm not sure about the differences. The 2 previous Highland like NC maps left me deep scars. The NC 6 was first attempt for Monarch level and failed because AI dow upon demands rejection. And after 3 tries, I have yet to finish my campaign there yet. And NC 20 featured an extremely late conquest for all my NC games except for space attempts. So, maybe I'll try this one again on Monarch again since normal Monarch setting is not challenging anymore. And I'm not willing to move the Emperor as 5 is coming out.