To motivate recent changes patrolling, create a tool that displays per-user review stats and ranks users by their review activity. This is intended for FlaggedRevs wikis although if it's easy to make it work elsewhere too (using patrolling actions), that would be a nice extra.
Features:
* count non-automatic reviews done by a user
* filter on time period (this week, this month, this year, last 7 days, last 30 days, last 1 year, all time)
* rank users by count
A similar tool (for plain patrolling, not FlaggedRevs, I think) is [[https://tools.wmflabs.org/patrolstats/|patrolstats]]. There is also [[https://en.wikipedia.org/wiki/Special:ValidationStatistics|Special:ValidationStatistics]] but it only displays stats from the last hour so it's not really useful.
This should probably be a Toolforge tool, although if it turns out to be easy on the DB, it could just be added to Special:ValidationStatistics.