Current synapse-task implementation has used quartz 1.6.0 version which is something old. The quartz latest stable version 2.1.1 seem to have many functional improvements and new features over 1.6.0 version. So it will be a good idea to upgrade quartz version to 2.1.1 to have future enhancements in synapse-task.
Refer to the document what's new in quartz2 
I would happy to provide a patch for this.