[uptime]

Add keys to existing nodes mostly. Possibly using tasks.openstreetmap.org and/or possibly doing something in a batch if I can get data from the city to use. These structures seem well defined, thankfully. And the crossings and signal locations look to be complete.

[matkoniecz]

In this case I would strongly encourage to start from manual mapping. StreetComplete Android app may be useful here (disclaimer: I am involved in making it).

See also https://wiki.openstreetmap.org/wiki/Import/Guidelines before importing data

[uptime]

Thank you!