MS Estonia and Rotated Dungeons

MS Estonia was a passenger ferry that sank in the Baltic in 1994, with 852 of 989 persons aboard perishing.  I stumbled upon a rather horrifying account of the sinking and there were some bits that stuck out to me as dungeoneering-relevant.

The interior hallways of the accommodation sections were windowless, fluorescent-lit passageways, smelling of aluminum and plastic, and barely wide enough for two people to pass. They ran fore and aft, and had branches from side to side. With their twenty-four-hour lighting and long rows of anonymous, closely spaced cabin doors, they gave those parts of the ship an institutional allure not much different from that of modern prison galleries. Moreover, the cabins themselves were smaller than cells, and though this must have been unimaginable to even the most miserable of their occupants that night, many soon turned into traps and then coffins...

She left the pub, walked forward past the information desk and up the main staircase, and went directly to her cabin, on Deck 6. When, shortly thereafter, the ship heeled over, her door popped open and she fell backward in her cabin and was pinned by gravity against the far wall. Because she was determined and nimble, however, she managed to emerge from the trap, to negotiate the tilting hallway, to climb to Deck 7 and the outside promenade, and ultimately to survive... 

[As the heel approached 90 degrees] The starboard cabin doorways now became chasms that had to be jumped across. Passengers who failed fell into the cabins, and some did not emerge. The transverse corridors became dangerous shafts, dropping away to the starboard side. Though no witnesses of this survived, after seawater began to enter through breaking windows, those shafts became deadly wells.

Takeaway 1: I am now looking at every room I enter and going "If this room were tilted 90 degrees in each direction, how screwed would its occupants be, assuming it held together?"

Takeaway 2: I've always had trouble justifying the use of pit traps.  But taking a sensible environment and then rotating it 90 degrees around the X or Y produces a totally reasonable justification for deep, deep pits and floors full of "trap" doors.  I think 90 degree rotation would probably be the easiest to work with, on graph paper or isometric mapping, and in play.

A highly-vertical environment without stairs seems ripe for OSRy play with emphasis on mundane gear.  Bring lots of spikes, lots of rope, maybe some planks to put along the edge of pits.  And it would give thieves lots of opportunities to scale sheer surfaces, as well as giving some play to abilities like Feather Fall, Levitate, and monk slow-fall that don't see much use.  It would also be a good excuse to play with altering hallway width and height.

What does the ecology of a highly-vertical dungeon look like?  Down in the pits, you probably have a lot of undead and dumb scavengers like mold and oozes.  Along the main hallway levels and in rooms that used to be tall but now are wide are your demihuman lairs.  Up in the top levels that can only be reached by sheer climbing, you get flyers and things that climb like spiders.

One sort of puzzle in stocking would be dungeon level.  Do you take the floors of the original environment and have that determine dungeon level, so your difficulty gradient is across horizontal movement in the rotated environment?  This seems like it would make it easier to keep organized (if your map is of the original environment and split by level there), but might also make it easy to stumble into difficult areas early.  But if you have deeper equal more dangerous in Z-space, then it's easy to fall into more difficult areas and not be able to return, in addition to being harder to keep organized.  Maybe you just make the whole space roughly the same difficulty...