It would be really awesome to have a post-Publisher field for when both the Publisher is done and the corresponding WSYNC finishes to run a script.
For me, it would be a cleanup script to remove old/unused updates from the Deployment Packages and maybe trigger Bryan Dam's WSUS maint. script.
Bonus: Make 2 of these, one for Scheduled Syncs and one for Manual Syncs.
The quick solution for this would be to create a scheduled task that occurs when this event ID occurs. See the photo below for an example.