I believe that is will be an amazing module. I love the concept, and I am willing to give any ideas I can. But for now, here are my thoughts:
Repetition:
A big 'No' when it comes to game development is repetition. Repetition is often a problem in most RPGs, since to become more powerful, players 'farm' experience. This results in players (when not using some sort of automated bot) running around killing monsters to gain experience so that he or she has the full capabilities of defeating the boss. A good difficulty slider can mitigate this problem, but I suggest that we look into making sure that the game is not too repetitive, since this will be the weakness of this module.
Difficulty Slider:
A huge difficulty is the RPG element. The world generation will not be a problem (I think), but the generation of items and enemies will be a problem. We would not want first-time players to face very difficult enemies or have the first-time players finding some OP item so that leveling-up becomes unnecessary. We can do something with time, such as "By X minutes, the player should be ready to take on enemies that are much more difficult, and thus should be given better equipment in chests for future combats," or by level "If the player reaches level X, spawn better items and harder monsters."
Multiplayer when the Module has a Win-Condition:
Although this may be later into the development, an amazing multiplayer could arise from this module. Multiplayer would probably have two versions: 1) players can unite to survive and 'win' the maze or 2) the players can race to see who can defeat the boss first.
Multiplayer when the Module has no Win-Condition (When module is WAY into development):
I thought that this module would be cool if there were like factions within the mazes. Faction members will have their names colored representing the faction color. Instead of killing monsters, factions can raid each other, and a faction can be 'taken' if a core block is broken (core block should take a long time to break). In this version, killing monsters would provide great benefits for a faction, so that factions would want to kill the monsters. Thus, an in-game announcement of "Epic Monster Spawned @ (some location)" can be made to prompt factions to fight to get to the monster first. To make things fair, only one faction at a time can fight the monster in a room, meaning that other factions cannot interfere. During the duel however, factions must make sure that their base is not compromised.
This idea can be fun by implementing a system of jobs, either by a
module or just verbally within the player community in-game. Some could be soldiers, some could be scouts, some could be resource-gatherers, and more.
These are all the ideas I have for now, but I will be sure to think of some more later! Anyways, I look forward to this module coming to life!