On Ask Different we have every month, a report posted on Meta for the whole month.
Most active users stats
Stats for all review queues
Highest voted questions
Highest voted anawers
Highest viewed question
This report is really good for:
Rewarding active users
Seeing review queues statistics
Seeing moderator activity like flag handling time
Seeing the food questions and answers
So I suppose bringing them to all sites. A moderator would need to volunteer to do that once a month. Every sites report could be slightly different as long as it aims to see everyone's success and the moderators work.
Note this is optional and just a suggestion.