I usually have two fortresses in one.
One is the Surface fort which is very slum like with poor living, death and terrible food, rubbish clothes and little luxuries. I call these Dwarves "Unproven." They have to prove their worth to my society before they enter the fort proper (or survive for long enough). They usually get the dangerous jobs. They don't get buried either, just have their bodies tossed into a heap at the side of the road.
The Deep fort goes the completely opposite way: Multi-level halls, double-helix entry ramp with glass dome, smooth and engraved floors/walls, personal 3x2 rooms with good furniture, nice clothing (sometimes dyed if they are really lucky) lava under glass floors, gold statues, the lot. Excellent healthcare and grand food. The Proven dwarves usually have pets too and so are generally happy.
All Dwarves, including Nobility have to perform in the military for at least two seasons, complete with danger rooms, swimming training, live training. The better the warriors, the better their equipment. (Unproven militia usually has leather armour and whatever weaponry they can get, but the Proven gets iron and then the truly proficient soldiers get steel.) Training is brutal for the military but it pays off.
My dungeon is bleak, chained to a narrow walkway, abysmal conditions and I have the option of containing and killing them if they tantrum. POW's get it even worse. Chained to the outer walls or stuck in cages or used as live training dummies. Or if they are lucky, fed to whatever beasts I keep as pets. Sometimes I wait until they are beaten to a pulp, then call off my warriors and take them captive again, just to prolong their suffering. Oh and Elves... I usually hold them captive and torture them for giggles. Then I either chain them to the Throne room pillars, or kill them and decorate the throne room with their skulls.
On the outside my society is bleak and holds little hope for my dorfs until they prove themselves, then they live in luxury... The trick is just to survive that long...