Corpses in the Valley of the Dead, or at least corpses created in the Valley of the Dead, should be preserved indefinitely without rotting away. This could be implemented either by simply keeping them fresh and unaging, or they could get completely rotten and bad to eat, halting just before they would have rotted away completely.

Not specified if this would have an effect on wraith corpses from the Valley’s graveyards, which instantly rot away if they produce a “Blecch!” message.

The priest of Moloch in the Valley of the Dead should always have a cloak of magic resistance, to guarantee that there is a source of magic resistance in the game even if the player is playing wishless.

There should be some way to enter the Valley of the Dead without requiring fighting through or looping around the Castle, in order to allow a player struggling to get up to the Quest experience level threshold to access the resources in the Valley.

Add a side branch that can only be entered by dying in a certain place such as the Valley of the Dead, or by life saving not working. When you die, you appear there with no inventory and have to fight your way out to return to your body. Monsters are also subject to this and appear in that branch after dying to the same conditions. However, it only works once - if you die again you die for good, even if you successfully got back to your body in the process.

Before you first enter the Valley, demons and undead (chosen from the graveyard monster algorithm, though perhaps excluding wraiths) continually spawn in the maze on the right of the Castle and try to path towards the upstairs. Also before it is set, in the Valley, awake demons and undead will try to path to the upstairs if they have nothing better to do.