Dark Fortresses: I want to be able to enter a Dark Fortress and see what the Goblin Industry has to bear - Huge Furnaces and Rows upon Rows have Metalsmith Shops, plenty of Clothiers, Weavers, and Leatherworking Shops, whatever the Goblins Cultivate/Fish/Hunt, and enough Mason's Shop to leave a Dwarf in Awe. I want to see horrid living conditions on par with the Humans (which btw should be improved sometime in the near future) and giant displays of military hardware, steeds, siege weaponry, and troops. I want to see the 'Dark Fortress' of War, Agony, Pain, and Impending DOOOOOOOOOOOooooooooommmmmmmm.........
Mountain Halls: Could care less but it should probably be 3-10 levels deep, consisting of an appropriate assortment of Dwarven Industry, Improved Living Standards of the Races, Grand Halls for Dining & Leisure, and ample Dwarven !FUN! Additionally it might have it's own interior catacombs, mines areas, and prisons.
Both Dark Fortresses and Mountain Halls would also have their underground tunnels or cavern entrances as well if appropriate to the size of the population or site, and the proximity to other nearby sites that dig below into the ground.
Forest Retreats: I could really care less but if someone gives me some Elves spawning in an area, I'm good.
Caves: The Caves need to be actual caves, and potentially they need to incorporate a bit more of a homely design. Kobolds might have central gathering halls, some primitive industry, primitive traps and defenses, some sort of primitive vault, and appropriately dedicated training areas to hone what few practices they employ (Sword, Spear, Bow, Ambusher, Knife User, etc).
Camps: I don't mind having some of the current campfire camps being left over for a few lowly bandits, so while the new ones I think are nice, some not-so-challenging ones should be left around too.