Wayfarer challenges/events improvements
I direct this feedback to @NianticTintino as I understand they're the one leading Wayfarer project.
Wayfarer challenges; users like it because they see a different part of the world for once and get nice rewards, Niantic likes it because they can direct the reviewers to areas that need it most. Win-win. However, the way these events are organised are not very user friendly. They require people to reset their bonus location but not able to set it back, they often exclude people who don't (or don't know about the event because:), it's organised through a forum not all people frequent, rewards are not handed out properly, rules are unclear, etc.
The solution: I think the Wayfarer software itself should be able to facilitate events. It should pop up as a status message when an event is available, and when activated by the user who chooses to participate it should set the location automatically, and it should present at least 25% of the review cases to the participating reviewer. When the event is over it should set the location back to its original place. There should be a separate part of the Wayfarer site to watch results and statistics and see how much is left to review to make it to a certain tier and a countdown to the event's end.
If you build in the capacity for events into Wayfarer, you'll see that you can issue events effortlessly, even create mini-events during weekends. Abandon these messy forum organisations for events and focus on a systematic solution that's durable and reusable.