Map for a flooded fantasy world. Largest landmass is the size of Britain.

[jbgibson]

So not as a specific proposal, just an example of island groupings, is something like this appropriate? The largest island is about 800 miles across. Generating a world with Fractal Terrains with a typical land extent of maybe 35%, I then raised the ocean till I got island chains. One can edit the roughness, and one HAS to edit in some linearity, like one kind of expects - island arcs. But leaving aside any specific shapes, does this look like too broad a chunk of planet -- too distant for your folks' navigation? Is it too close? The same sort of archipelago(s) can be scrunched closer or I could show a whole world. I included a blown-up section so you can see there's lots of smaller islands - a reasonably realistic situation.



From those kind of shapes I can generate stuff like