In-game using the map when zoomed out the lines for roads disappear:
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However, in 3DEN when using the terrain textures it shows the roads regardless of zoom:
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It would be nice to see a way to turn this on or off, either scriptable or in settings. The map with the roads drawn regardless of zoom looks very nice and is easier to use when planning routes. On top of that, this seems to be an easy to implement addition.
Edit: The 3DEN map also shows forest areas, not a needed addition but its another difference not present in the in-game map.