I'm going to make a fortress OUT OF GLASS. I'm making a crude dome-like shape (more like a pyramid). I'm treating anywhere outside the glass containment as the vacuum of space. A 10 tile long tunnel 5 tiles wide will have two drawbridges to form a crude airlock system.
The fort itself will be lain out like this, going from the ground up:
Ground Level: The Main Hall will be here, with the well inside the hall. The trade depot will be here as well. There will also be about ten beds for those without living quarters. Steel corner turrets will contain one catapult and two ballistae.
Barracks: 5x5 tile rooms with beds on the side and an extra row of beds 4 tiles long in the centre. The walls will be made of incendium for warmth.
Mess Hall: Three kitchens, 2 tile wide rows of tables with chairs next to them. A row of tables and chairs are in front of the kitchens.
Hospital: Individual 3x3 rooms containing a bed, steel table, and a chest stocked with 30 rolls of thread and 30 pieces of cloth.
Armoury: Weapon, armour and ammo stockpiles will be here. Nothing more.
Observatory: This room will take up as many z-levels as necessary to go up to the top.
Military:
Stormtroopers: Incendium armour and mask, with a steel crossbow firing blazing incendium bolts. Basic military soldiers, trained in underground firing ranges.
Plasma Troopers: Levisium armour and mask, using wrought iron crossbows and glacium bolts. Secondary trooper, trained in the same manner as stormtroopers.
Laser Swordsmen: Incendium armour and mask, with blazing incendium long sword and glacium roundshield. Reserved if outer defenses are breached, trained against unarmed captured invaders.
Plasma Swordsmen: Incendium armour and mask, with a glacium long sword and glacium roundshield. Same purpose as laser swordsmen, trained in the same manner.
Food and booze will be kept in underground stockpiles. Prepared meals will be kept in the mess hall, and will consist of stews.
Siege engines:
Laser Cannons: Ballistae firing bolts with blazing incendium heads.
Plasma Cannons: Catapults, basically.
Living quarters will be connected to the main fortress by 2 tile wide tunnels with walls and ceilings of glass. Rooms will have steel doors and walls. Because space is so cold (hovering around Absolute Zero), floors of rooms will be made of incendium instead of the usual glass. The farms will be encased in glass and will be called 'Bio-Domes'. Food will be grown above ground in the bio-domes. Underground farm plots will be dug under the underground food stockpiles.
I use the Civilization Forge mod, so this challenge may not be possible in vanilla DF. I've also made the buildings spew out the metals, so I can have easy time building my settlement. Stone for the plasma guns, however, will have to be dug for. The mineshaft will consist of up/down stairs, and 1 tile wide shafts to wander through. The steel up/down stairs in the glass fort itself will be surrounded with steel walls and a steel door on one side. The shaft will be called the fort 'elevator'.
Any positive thoughts about this are proudly accepted. If you are thinking negatively, don't post your thought.
EDIT: To heat an entire complex of either the fort itself or a small building of living quarters, a solid 5x5 block of incendium will be built in the complex one level under the building in the exact centre.. To fuel the whole fort, a 3x3 room will be set in the exact center of the main hall, with a wood furnace to burn wood as fuel. One log will be fed to the reactor per season, otherwise all heaters will cease to function and the production buildings will be useless. If the reactor is a charcoal furnace, one log will be fed every two seasons.