You know, on the topic of dungeons, though, I had a suggestion a few months back involving
Raw-Generatable Procedural Maps. The basic premise is that we could generate player-created rooms, buildings, ruins, whatever, make them in raws, include modular pieces inside those rooms and buildings, and then use procedural construction based off these raws in worldgen.
This would mean that a modder could create a new race/civilization, give that race their own particular style of archetecture by settting a bunch of variables in how the procedural generation works and making a few raws for building floor plans, and we could wind up with a host of player-made architecture styles.
Basically, if we applied this to dungeons, we could potentially literally make some NetHack style dungeons, created by specific modded-in races of beings that still inhabit their fortresses and protect them. And then we could all share these dungeons we built over DFFD, and some people might make super-mod packs like what Genesis Mod does by combining enough little things to make dozens of mods into one giant package. Basically, we'd eventually have some super "Adventurer's Tour" mod, where multiple procedurally-created castles and dungeons pockmark every corner of the map.