So this got me thinking: wouldn't it be great to extract from old maps the fonts, and styles, etc (the repeating elements), and apply these styles to the data underlying modern maps (imagine Google Maps in medieval style!). It would be useful to have some software to help automate this, but I suspect it would need significant human supervision.
This concept is expandable to other diagrams that have repeating elements. The most obvious of this is generating fonts from the writing of old books - and not necessarily just the printed ones - e.g. a font based on the handwriting of 15th century monks. There are other old documents/images with repeating elements e.g. building/engineering plans.
An interesting artistic use of this would be randomly generated maps, using the old styles, as image content for digital wallpaper.