OK, at long last I've been getting to a finalized idea for the game I want to run. It's going to use ACKS as the rules system, in part because I am happy about the way that it handles economics. I also find that it takes a reasonable middle ground on the whole "character build" issue - in fact, the way that it handles Proficiencies resembles something like the Kits of 2E. Kinda. Finally, it makes explicit the "endgame" of character involvement in the larger scale politics and such of the game world. I hope to eventually get to the point that some characters are playing on that level. Unlike my previous attempts to get a game going, this one is a) under a time constraint, and b) actually has lines and words set to paper already.
Anyway, the setup is that the characters will be backwoods yokels new come to the big city. Well, the Provincial capital, anyway. Not far from the capital, there is a large mound, similar to Newgrange in Ireland. Of late, there has been an increase in goblin raids, stealing children and livestock. The shepherds in the area claim that they have seen goblin raiding parties coming to and going from the mound in the moonlight. There was a time when the elves made a stronghold of the mound, but they seem to have abandoned it for some unknown reason. (This is, of course, the tentpole megadungeon. It has many secrets, and one overarching mystery: what happened to the elves?)
Meanwhile, orc warbands are harrying the villas and towns on the fringes of the Empire. Strange prophets stalk the streets of the cities, proclaiming that the end of the world is coming. Religious cults attract increasing numbers of adherents, threatening the stability of the ancient Tetradic Church, and perhaps hiding darker secrets still. Missionaries of the Fatalist Church of the eastern realms have come to the cities of the Empire, as well, bringing their message of submission to Fate. Certainly, the Empire seems to be in upheaval, with change being the prevailing wind.
The larger world will either use the Terra Ultima map (also called "Pangaea Proxima") or an older map I have wanted to use for a long time. The older map was inspired by the game Lords of the Middle Sea, which is basically a map of North America with the coastlines set at approximately the 1000' level (though the Middle Sea map also includes the idea that a large section of the Midwest collapses, for reasons due to the fictional background on which the game is based; I wouldn't be using that idea). For instance, in California, the Bay area becomes the mouth of an inland sea, which covers the area of the Valley. If I use that map, then the campaign city will be about where Seattle is in the real world, with the Olympic Peninsula becoming an island off the coast. If it ends up being the Terra Ultima/Pangaea Proxima map, then the city will most likely be located in the region that used to be Hudson Bay, Greenland, and such.
The idea, then, is that the Empire is dying due to being torn apart by both natural and supernatural forces (and other, secret reasons as well). The Emperor is weak and controlled by the Kings of the various provinces. Elves and goblins, orcs and tribesmen all threaten the areas that the Empire cannot directly control through its military forces, and are starting to threaten the areas that it can. The players may be able to, if not stem the tide, at least hold it back for a time. For many people, that time is all that is needed. Heroism can be as simple as making the life of the people better for a time. Maybe the players might even build something that can outlast the fall of an Empire.