(Cross-posted in Roleplaying Games.)

I'm designing a game setting and need help brainstorming pantheons, names, religions, afterlifes, and associated myths. Any help will be appreciated.

Here's what I have so far. It's long, but I'm looking for brainstorms, so don't read all of it; just skim it until something pops out at you:

Most of the religious history will have SOME grounding in truth, but be distorted with time.

Humans are the only native race of the plane. All other races were originally extra-planar, but have been settled for generations and no longer have a living memory of Somewhere Else. Nevertheless, their myths will usually incorporate some story of exodus from one point to another, with a grounding in actual history but little to suggest planar travel.

Most gods are actually elevated by mortals, usually raised up to their status by respect and worship (or fear and infamy), but sometimes by this artifact or that acquisition of limitless arcane power. Of course, some of those gods have been gods for a very long time.

That said, I need several pantheons, each with a different character:

Humans: The human race's history is one of being first colonized and exploited by the demi-human races, then overrun and enslaved by the savage races, and finally clawing their way to freedom and dominance of the plane. The Human Pantheon is ultimately about serving humankind, and all other races can look out for themselves, or possibly die in a pogrom. (This is one of the points of doctrinal dispute within the Church.) The chief deities of the Human Pantheon are the Twins, a legendary brother and sister who dragged humanity kicking and screaming out of barbarism and into civilization before themselves dying in the pivotal battle against the savage races. Elevated to godhood postmortem, the Twins have in turn taken to elevating those humans who create some monumental advance or benefit for humanity -- the general who conquered and converted half a continent, or the first blacksmith to figure out and codify iron-working, or the legendary doctor who laid the groundwork of the healer's trade. I don't have details on anyone other than the Twins, though.

Elves: Elves are scattered across the world in isolated colonies, each devoted to perfection in a different ideal. (This accounts for the wide variety of elves. One colony's spent generations trying to be at one with nature, while another has mastered the arcane.) They typically remember their home plane as an island that vanished beneath the waves, and most extraplanar travel is referred to in terms of aquatic voyages. The head of their pantheon is the Emperor at the time their home plane was destroyed, and some say He carved a piece of land free of the doomed island and placed it in the heavens instead, though this is disputed. Elves probably honor overachievers like humans do, but again, I have no details. Expect a lot of variation from one colony to the next.

Dwarves: Dwarves originally came from an "Inner Earth" type plane (a shell of rock around a central sun where gravity pushes them "outward"). They tunneled their way to other planes, and their migration tales are of journeys through deep and dark places. Originally they made regular pilgrimages back to their home plane (which they called Inner Light) as a religious obligation, but when that plane was overrun by savage invaders and the tunnels began spewing forth twisted beings, the dwarves went through a doctrinal change. Inner Light now refers to a spark of divinity, determination, and potential within each dwarf, and the pilgrimage is meditative in nature. I'm utterly flumoxed about what sort of gods to give them.

Gnomes: Gnomes believe in the elevation of the world through figurative levity, and its fall through figurative gravity. Seriousness and dourness sends the world spiraling towards destruction, and laughter and humor is the key to salvation. Gnomes have an animistic view of things -- rocks and mountains and animals have spirits, and the embodiment of an entire class of spirits is a god. Thus, Mountain might be a god and Fox might be a god, but these are assembled out of the combined spirits of all mountains and all foxes. Again, I don't have details, and suggestions for fables would be awesome. Their name for all the land (and the plane at large) is Old Stoneface, and the highest calling in their faith is to produce a joke or prank so amusing that Old Stone Faith (and thus the entire world) must laugh. Gnomes are closely connected to fey, and their trips (in multiple senses of the word) may have involved wild parties with satyrs and rings of mushrooms.

Halflings: Though the typical halfling in their home-plane was very much a sedate, respectable home-body (think hobbits), those who ended up in humanity's plane were the minority of restless wanderers, the exiled troublemakers, and so-forth. Halfling religion on the human plane is upside-down, with the domestic gods that were the traditionally-respected figures now reviled, and the rebellious, trouble-making gods representing the ideal. No clue at all who these gods are, though.

Goblinoids: Originally, goblinoids were part of a three-caste society (priestly bugbears, noble hobgoblins, and commoner goblins). Almost the entire race was twisted into evil with the destruction of their home-plane, and they lost their good natures and identity as their emigration swept across countless planes in one bloody, barbaric invasion after the next. Nowadays goblinoids only remember a smidgeon of their origins, but I want to know their original religion. Something which speaks both to the goodly beings they once were, but also can be seen, here and there, in the twisted beings they've become.