Make the Gnomish Sewers Mines’ End in EvilHack less aggravating for the player who lacks teleport control: instead of having to jump into teleport traps and teleport around the level randomly until winding up in the hidden luckstone room, make one specific teleport trap always direct to that room.

Polymorph, teleport and levelport traps should disappear once used by any monster (including the player). Or else they have a low-ish chance of disappearing per each use.