The only AU that has a predictable naming scheme is Brothers Asunder, because it follows Bowman of Wellwood more than it followers the other Brothers AUs.
So for the last two in BAsunder, they’ll go (name) of (place), and the place can be many different things.
Others that occasionally (but not always!) follow a naming scheme are Oscar stories. He often gets names that are (food) and (monsters), though some of his will deviate from that style. It gives us classics like Hershey Kisses and Salt Lines, along with Garlic and Cold spots.
The rest of the story names are very open. They can be song lyrics, inspired by the story or other songs, or even a play on book names.
Brothers Apart 