They should really find some better examples other than 3D models that were just imported into Minecraft... why bother? Why not just print the original 3D models? Show me a 3D printing of someone's original Minecraft lair that they would be proud of.
The companion cube was selected because cubes are often used to test a 3d printer (http://www.thingiverse.com/thing:477) while the enterprise was selected to test whether the script was capable of handling something on a rather large scale with high complexity.
Now that the tests are out of the way, it's time to print the lairs and cities of which you speak.
