*muttering* Okay, I had a nice long post that I was just about to copy and paste, decided to try spell check, and popup blocker refreshed the page and killed my post...so here goes again, but forgive me for the short explanations, vice the more creative descriptions I would have posted.
And in advance, thanks for running the game! I super appreciate the time that goes into it, as I've run a game before.
I have come down to 4 concepts that I'm submitting for approval. All are rogue/wizards, aiming for arcane trickster. In no particular order (as I think they'd all be fun to play.):
First, Drow, chaotic neutral, worships god(dess?) of luck, flips a coin for some decisions, which lands him on the town's side of the conflict.
Second, Svirfneblin dude, hates living underground, gets chased by Drow to the surface, barely escapes, and stays up here to explore this "huge cavern."
Third, (I think I like her best.) a chaotic good tiefling girl rogue, who is curious to the core. Tries to learn wizard's secrets, gets caught, he decides he likes her, takes her on as his apprentice.
Fourth, grey elf half-dragon (copper), chaotic good, kicked out of mom'n'dad's metaphoric nest, making his way in the world. A bit snobby, as grey elves typically are, especially when they've got a dragon for a daddy and a fairly high IQ.
If you don't want anything with a level adjustment, then would you allow the paragon classes? 3 level prestige, based on race, which gives some nice racial improvements.