My own dungeon: bottoming out

OK, we're working on my own little dungeon project.  We've done the first level, the second and third levels, the fourth and fifth, and the sixth and seventh levels.  Now we’re all the way down to the eighth level.

cloud giant 1

cloud giant 1

dragon (any) 5

dragon (any) 2

frost giant 4

frost giant 2

spectre 9

spectre 10*

spectre 9

black pudding 1

chimera 3

dragon (red/white) 1

evil high patriarch

evil lord

evil wizard

hydra 5, each with 5 heads****

ochre jelly 6**

stone giant 6

troll 9**

vampire 3

*extrapolating from Holmes, doubled number of seventh-level monsters on eighth level

**extrapolating from Holmes, tripled number of sixth-level monsters on eighth level

****extrapolating from Holmes, quintupled number of fourth-level monsters on eighth level

Half my rolls to determine which level to roll on were 10 or higher, meaning half of the encounters on this level are with ninth-level monsters.  To make this level semi-survivable, I’ll have the EHP, lord and wizard each lead one faction against the other two.  The patriarch directs the vampires and specters, while the evil lord leads giants and the wizard employs the trolls, chimerae and the solitary dragon (let’s make him a charmed white).  Also, per my note from my expanded wandering monsters tables, the name-level characters will get some underlings as well.  The grouped dragons (rolling randomly)—5 brass and 3 red—are sworn enemies, and the pudding and jellies scavenge the caverns, with the trolls just trying to stay out of everyone’s way.

Next, we turn to the ninth (and last, for now) level:

black pudding 2*

black pudding 3

displacer beast 27**

displacer beast 15**

evil lord

evil lord

basilisk 8*

cloud giant 1

dragon (black) 4***

dragon (white) 6*

evil high patriarch

hydra 5 with 7 heads ****

manitcore 20***

master thief

purple worm 1

stone giant 12*

storm giant 1

troll 30*

vampire 2*

wraith 15****
*extrapolating from Holmes, doubled number of eighth-level monsters on ninth level

**extrapolating from Holmes, tripled number of seventh-level monsters on ninth level

***extrapolating from Holmes, quadrupled number of sixth-level monsters on ninth level

****extrapolating from Holmes, quintupled number of fifth-level monsters on ninth level

Interesting … OK, the master thief (and his poison-wielding assassins) guard their hideout with a lot of traps that use black puddings.  The black and white dragons are in constant conflict, while the storm giant leads the stone giants in digging for a lost artifact.  The EHP controls the wraiths and vampires, while the evil lords (husband and wife) guard their quarters with the hydrae.  Displacer beasts, basilisks, and manticores all have their own breeding grounds here, and the trolls have a lair (borrowing from Holmes’ approach to humanoids, I’ll give them a king who fights as a hill giant).  Everyone leaves the purple worm alone.

So that's as far as I'm going with this thought experiment for now.  We have the bare bones of a dungeon; let me know if you'd like to see me flesh it out.