If 1 grid square equals 1 meter, I tripled the size of the world from 1024x1024 meters to 3072x3072 meters. This on-foot high-speed adventure gives a small sense of the vistas and scale of Britannia currently.
Truly I would like to eventually make it bigger, maybe 5kmx5km, but things like that can always be done later after the game is functional once the important areas are filled out.
The goal is to get the game up and running, then making it prettier is just extra bonus stuff. It may be the case the map is best served by shrinking it, and that's good, too!
Here's the original fb UDIC post.