Thanks for the ideas, Zaer... but I was looking for something on a bit smaller scale.  The adventure will likely all take place in the Icalein Peninsula (which I'm picturing is about the size of Florida - I'll edit that into the description).  Still, should the campaign expand past my initial ideas (the story arc I'm planning will likely take us to about level 7 or so, but that's just a rough estimate), I'll keep those locales in mind.