Yea, need to flesh out the setting a bit more. I'm fond of magic, since it allows things like airships and other fantastical machines without having to explain much.
We also probably want to nail down some common places where the characters will be at, say like describing the airship, maybe a pirate city of some sort and a legitimate city. Just so we're not scrambling to make stuff up later on.
As for characters, I haven't really thought up much yet. Usually I like to see what the setting is like and what other people are playing in order to get some inspiration. Do you have a character in mind?