I think a gym challenge would be a good idea. It sparks interest and activity (hopefully) and it makes people interact with each other. Not to mention, the gym leaders are actual people, so there is an authentic challenge instead of fighting npcs.
This is an idea that comes up on occasion. We used to have a gym challenge here years ago (before I first joined). However, it ended due to a lack of overall popularity and participation. We will definitely consider the idea of having event-based gym challenges though, thanks for the suggestion! This idea sounds intriguing. Would you mind going into some detail about what kind of treasure hunt you're thinking of?
Okay so, it's summer and that means time for ice cream and cool treats! So, how about the staff member/s hide some cool and colorful candies/popsicles around the lake and the other members go on a treasure/candy hunt? And the rest is understandable; the prizes and winner places and stuff.
How about a trade day once a month/year/other period of time? You could trade Pokémon from the catcher with someone on the site.
I want to suggest. An event where eggs appear more frequently. Maybe about twice as much as original. during Easter