Fire & Ice.
The current state of the game being what it is, I haven't been playing DF, but been experimenting with the world gen very much.
I tailored a medium sized world with Human civilization filling the west, Elves to the East, Dwarfs to the North, and Goblins to the South. All of them grow into enormous sprawling civilizations. In the middle of the map, a grid of peeks, all with volcanoes, with mixed wild Evil/Good jungles.
This gives for fun embark locations, with a big mix of rock types, and multiple biomes.
In the example below, the embark has Freezing Obsidian Mountain (both a named peek and a volcano), surrounded by dense Warm forest. Glumprong and Featherwood right next to each other, accessible aquifer only in the evil biomes, completely FLAT forest!, tall mountain. My favorite find so far, so I thought I'd share it.
It also has the Temple. Yay!
Due to world gen parameters, the temple contains over 4 z-levels of undead, with over 100 z-levels of Fun below that.
Over 70 z-levels from the surface to the first cavern, plus the tall mountain, leaves lots of fortress room.
One volcano, plus 5 underground pipes.
This is a 8x8 embark, but all the best features fit in 4x4.
On embark, before even striking the earth, df process is using 1.4gb ram.
Site Finder Information:
Embark Location:
Notice the snow covered obsidian, but warm trees and grass.
View in Stonesense:
World:
Very Very Long World Gen Parameters download from Dwarf Fortress File Depot:
http://dffd.wimbli.com/file.php?id=2417