I'd say the latest version of the Zeitgeist Player's Guide has more than enough setting information on the countries and such that you could easily use it to craft your own adventures in the world.
The player's guide is really cool and I love the flavor that it does provide but it really emphasizes Risur and Flint while only glossing over the other nations. It'd be really cool if they did something like the Inner Sea World Guide but for the Zietgiest world.
