What are the essential elements of the most generic of D&D settings? You can, of course, dump just about anything and everything to create your own setting. But what I'm looking for here are the elements that scream D&D -- things you must have in a setting to have the D&D feel to it. Simultaneously, I'm interested in what things could be dumped without hurting the feel of D&D. What could you rip out and still have something that feels like D&D?
Here are some of my thoughts:
Dungeons -- while they don't necessarily have to be underground, you really need to have locations filled with monsters that the PCs can kill and take their loot.
Dragons -- one problem I had with 2e and now with 3e is that dragons have become unstoppable killing machines. (At least if the DM runs them right.) Whilst they were far too wimpy in 1e, I think it's a bit much. I hardly ever run a dragon in an adventure because I don't do TPKs. I think D&D needs more dragons back in the setting.
Adventuring parties -- there needs to be some reason for wildly disparate individuals to get together, go into dungeons, fight dragons, and take their phat loot.
Humanoids & demihumans -- D&D wouldn't be the same without dwarves, elves, halflings, orcs, and goblins, at least, as annoying as some of the racial stereotypes are. Not all of them are necessary -- who needs gnomes when you have halflings, or kobolds when you have goblins? -- but the concept of multiple humanoid races is pretty essential to D&D.
As for something that I think could (and should) be ripped out are all the zillion types of magic. Cleric, wizard, druid, bard, psionics -- one spell list would be much better. I'm not 100% satisfied with Arcana Evolved, 'cause I like the more bad-assed magic of the standard rules, but I think it is essentially a step in the right direction. D&D spells are complicated enough without the added, and to me unnecessary, complication of different spell lists.
So, what do y'all think? What would YOU say is absolutely necessary to a generic D&D setting?