Musings on Playing in the Dungeon

Like a lot of gamers, I am intrigued by a dungeon-centered campaign. And like a lot of gamers, I get stuck on things like realism (as in simulation, not the philosophical school), logic, etc. But my main stumbling block is simply keeping it fun and interesting. For me, this means finding ways to infuse dungeon-based gaming with some other concepts that add to or expand on the fundamentals of good dungeon play (exploration, encounters, and extractions). For example, what do you think of these ideas as a way to play out a dungeon-based campaign. I am just throwing these out there...I haven't worked through any of these ideas myself in any detail:
  • The Lewis & Clark Expedition: This expands upon the exploration theme. The idea is to equip a party for a long long unsupported adventure for the purpose of exploration. Of course, there would be encounters and extraction along the way. I like this in the abstract, but how would it work in actual game play.
  • Mt. Everest: Similar to the Lewis & Clark idea, but instead of a well-equipped party moving along as a unit, the party establishes a long-term base camp within the dungeon to use as a jump off point to explore and adventure.
  • Silk Road: The dungeon adventurers somehow get involved in economic trade that involves moving valuable goods from Point A to Point B through dangerous territory. 
  • British Colonization of India: The dungeon adventurers set themselves up as rulers, creating a mini-realm within the dungeon.
  • British Settlement of North America: The dungeon adventurers (and maybe their families, friends, and underlings) all move into the dungeon.
I am not sure if any of these ideas have merit or if they even make sense. I am curious to hear what you have to say about it.