I'm never sure about the terminology but what i meant by less saturation is more a lower opacity of the coloured territories like in these maps
by Levodoom: http://levodoom.deviantart.com/art/S...-old-436687735
or by ProjectWarSword: http://projectwarsword.deviantart.co...-Map-482223944

As said, it's more a thing of personal taste. Generally, i'm a sucker for more "subtle" colour palettes kinda like in this map by offeye: http://offeye.deviantart.com/art/Sta...-Map-298911855 (I really love aubergineish and pflaumeish colours ). But i'm fully aware that they often come at the cost of lesser readability.
Btw., when doing research for a space map some time ago, i stumbled upon this wonderful site: http://www.lcars.org.uk/lcars_Alien_panels.htm A real treasure trove for sci-fi colour palette inspiration ... it's rather Star Trek heavy though