This might be similar to something that's already out there, but I think people will be able to find it useful.
The spreadsheet allows you to view all of the important information for any empire state, all in one compact page. This eliminates the need of clicking between cities, trying to remember everything, and also checking the readme for trade route prices. I've also included a single map that shows where each playable province is located.
-Province location map
-Trade city info
--Cost to open
--Goods bought and sold
-Our city's resources
--Provided in the editor
-Distant battle info (city and time to reach)
-Invasion path info (how many and years of warning)
Version 2: Changed the format to PDF, as it is more common and the filesize is smaller, to boot. If you want the original spreadsheet, just let me know via comment, PM, etc.