What is great about Keep On The Borderlands is that it allows players to select the level of challenge they are willing to face.
Among the rumors provided in Keep On The Borderlands is that the deeper you go within the Caves of Chaos box canyon, the more dangerous the denizens. A cave mouth closer to the canyon entrance is less dangerous, while those at the end of the box canyon are likely filled with fearsome opponents, and fabulous treasures. The players can play-it-safe, and explore the nearer cave-mouths, or take a chance at the deeper ones. The DM can adjudicate the results of that player choice, free of any hint of bias, since it is the players themselves that pick the easier or harder road.
It is well-understood by all experienced D&D players, that the deeper within a dungeon you delve, the more dangerous the traps and monsters. Yet one of the design principles, regularly applied to dungeon creation, is that the stairs to the next-deeper level are difficult to discover. Call that what you like: I call it railroading.
Rather than hiding stairs to the deeper levels, i'm of a mind to have one staircase -- The Endless Stair -- that traverses the entire depth of the dungeon. Not a staircase that goes directly down mind you, but one that meanders, splits, crosses chasms, follows underground rivers, backtracks on itself, and reveals varying architectural styles at different points in its' descent.
As the stairs decend, there are dungeon levels hiving off in different directions, sometimes blocked by hastily-completed walls, or locked and barred doors, offering danger, mystery and treasure. There may be collapsed stair sections along the way, requiring magical or mechanic means of bypass, and portcullises on the staircase preventing immediate entry to lower levels for those lacking creativity, but there will be no question where those stairs are.
The only question ... for the players ... is whether they are feeling lucky today, and want to take a chance exploring lower dungeon levels in exchange for potentially higher rewards.