With enough effort, a stylesheet could do some rich text formatting like that, but it’s very involved. We’d need to think through the technical details. It’s a good idea design-wise. I’d suggest opening an issue about it so we can explore it further.
We probably will eventually have to grapple with the difference between a name and label. But in the shorter term, date ranges in name=* have been discouraged for a while and are now redundant to what most of our software can do automatically. We should start removing these date ranges from name=*.
When we implement localization for the main website, there will be an option under My Preferences. The embed site lets you override the language using &language= in the URL. Setting it to mul (the language code for multilingual content) reverts to name=*. We could look into something similar for the main site. Some of this functionality is coming from the openstreetmap-website project, where a similar feature is in the works.
Localized names can improve comprehension, especially when viewing places and time periods that use languages and writing systems very different than your own. Showing localized names will encourage mappers to add them and make it easier to maintain them. On the other hand, unlocalized names are also important for accurately and fairly portraying a place and time period, especially since some cultures have historically given some other cultures derogatory or offensive names.
Eventually, we plan to show both the name=* and localized name:*=* to provide the user with as much information as possible at a glance. One step at a time.
I think most these things are imminently feasible at this point, and the rest will be feasible once we get rid of Leaflet. We just need to hammer out the technical details and design and figure out priorities. (Localized labels are already several months behind schedule for our small development team.) Let’s continue these discussions on GitHub, since they aren’t specific to mapping the Holy Roman Empire.
