Looking for an elegant, low-level adventure

[Eldan]

If you know a bit about Planescape (specifically the city of Sigil) and aren't opposed to do some finishing work on it yourself, Planewalkers has a downloadable adventure called Desire and the Dead on their webpage.

It is based in one of the poorest districts of the city of Sigil, and the PCs are hired to generally keep the peace, hunt down a dangerous monsters and, more or less peacefully, deal with gang problems and a gang of dangerous lunatics. (There's more in the background).

It has, in my opinion, a lot of interesting NPCs and locations, and good roleplaying opportunities, if you take the time to flesh some of it out a little more.

The interesting thing about it, and why you might like it, is that it's almost entirely based on various random encounters you can throw at the PCs, some of which advance the plot, and some of which don't, and lists of locations and NPCs the PCs might see or meet.