I had an idea for a HUGE dungeon, that will appeal to fans of the original game as well as the RPG types out there.
The premise is this...
The Hall of heroes is the trophy room of Lord Chaos, the souls trapped in the mirrors endured a horrible half existence until Theron revived four of them and they defeated Lord Chaos.
However, Lord Chaos is insidious and as well as his backup plan (which is thwarted in CSB) as a last act of spite and malice before his defeat "tainted" the Hall of Heroes through dark sorcery and evil artefacts, driving the trapped souls contained within the mirrors to become corrupted and driven to madness, he then released them to wreak his revenge against the world for him.
Even the four who defeated him were not spared, for although Theron was able to grant them flesh and bone, he was not able to sever their links to their vacant mirrors, and they too became corrupted.
And so after the final defeat of Lord Chaos, and the withdrawal from mortal affairs of Grey lord, Theron was left with the difficult task of saving the world from those who had once saved it.
And with that Theron set about sponsoring a quest to either heal or destroy, the corrupted heroes of the dungeon.
That's the basic story, it would be a very large set of dungeons of different types (rather like skullkeep) with sections based in forests,swamps,dungeons,cities,tombs etc.
This is an idea I am throwing out to the community, I am still new to RTC and so my skills are very much those of a neophyte

If you are not able to help out with graphics, sounds, etc, then even advice on story and concepts, for instance what did each of the heroes do after their corruption? did some of them team up? do some of them fight amongst themselves?
I see Halk going off and becoming a savage barbarian warlord, who threatens civilized lands.
Gothmog returns to old and dark schemes, maybe rising to power as a fearsome necromancer or dark wizard.
Perhaps Stamm returns to the city of his dwarven kin and usurps the throne, (an evil dwarven city is a good idea for a dungeon).
I have hit upon the idea of using WOW model viwer (to produce custom made screenshots of world of warcraft characters to make anims and bitmaps, the graphical style is cartoonish, but so were some of the original DM graphics).