I would like to counter the argument here for more green worlds with...I have enough maps already for green worlds. What I am lacking is 'other' stuff.
As an example, in my home Battletech campaign, our Merc Company was hired to retrieve some documents from a cache before others got there. We got to the system, and randomly rolled for weather,etc to sort of 'set the scene' if you will. We got winter & ice. No Biggie, in the campaign it means we arrived at the region in winter, and thus all campaign tracks featured winter snow storms, ice, deep snow etc.
But Hey, winter/snow maps could also be for northern climates, or higher elevations, like the Swiss alps or the Himalayas.
Now, Also consider planets like Gliese 581d, which is thought to be a super earth, orbit within the habitable zone, but also thought by some always have one of it's poles always facing it's parent Star Gliese. This would mean, a planet like Gliese 581d, while Habitable, it would only be the Equatorial region as (for sake of argument) the Northern hemisphere faces the sun and so would be far hostile on the HOT end of the scale, the same could be said for the Southern hemisphere which would be far too cold.
And, finally and argument that not allll BT Battles would be for habitable places, but also those pesky but durn-it-all we NEEDS IT places like mineral rich regions (need all that metal and stuff for building these Hulking Monstrosities and cities and what not.)
Finally, let's take MECH WARRIOR ONLINE's recent map CRIMSON STRAIT:
http://mwomercs.com/game/maps/crimson-straitA cool Terrestial world, but the waters are red in color from the local flora/fauna.
So, put me in the camp wanting to see places other than Green Land, Blue Water.