Drunken dwarvish architecture.
Maw Of The Beastmen.
Mimeographing your setup.
Not-sense is not nonsense.
Sentence fragments bounce around my head when I look at the Caves of Chaos. Classic module, repurposed for the 5e playtest, I've never seen it before, no idea if it resembles the original, wouldn't run it as-is. I like the notes on Why PCs Are Here, and also the encouragement to play through it however you're inclined. That never hurts.
DRUNKEN DWARVISH ARCHITECTURE: Phrase coined by my wife to describe floorplans like this -- bad flowcharts of random boxes connected by random lines. Spaces nobody would live in; spaces that don't take life into account.
MAW OF THE BEASTMEN: I'm reskinning most of the inhabitants to manimalist hybrids -- ratmen, boarmen, etc. Not especially original either, but more exciting than yet another warren of orcgoblinhobgoblingnollblaaaarrgh. Plus assigning them to familiar animals will make it easier to improvise details about their lives, lifestyles, living quarters, preferred food, and all the other stuff that my players will want to know. Please let's not keep moving PCs through arbitrary underground deathtraps populated by the same old same old. Sucks the sense of wonder right out of the room.
MIMEOGRAPHING YOUR SETUP: This place is Levittown for humanoids. Entrance, guardroom, another guardroom, maybe storage, chief's quarters, big warren for everyone else. One race might live that way, maybe. Six wouldn't.
NOT-SENSE IS NOT NONSENSE: There's a difference between "dungeons are different and weeeird and reflect our unconscious surreal fears" and bad layout. This is bad layout. It just doesn't make sense, and it's not interesting enough to be nonsense.
I'll still run it for the wife and kids. We'll test-drive the proto5e mechanics. I hope that the next playtest phase moves out of the dungeon -- an updated Isle Of Dread would be pretty sweet.
What would also be sweet is the inclusion of the Keep On The Borderlands that was originally near the caves.