Periodically sample and record all configuration settings, including command-line options, dynamic parameters, hidden parameters, and internal storage engine parameters.
Capturing these every 15 minutes or so in the log file may be adequate. (May as well also report the DB version at the same time, and the storage engine.) Including them in FTDC would be nice.
People often work with small slices of logfiles; when viewing a partial logfile, version and configuration information is often unavailable.