Hi - I am not sure if we should go in this direction but at least wanted a discussion.
As part of the Station Information System project, we had to extend the FDSN StationXML schema significantly because we needed to load equipment information from the seismic installation as well as the response it produced.
SIS Extended StationXML
Should we consider modifying StationXML to allow this type of information? Installation information is very useful not only to network operators but also to certain researchers.