It's time BB adjusted the loot and/or XP gains for adventures. It would be easy for developers to measure:
- Count the number of adventures given out over a fixed time period e.g. 14 days
- Count the number of adventures started/completed in the same time period
For adventures that were rarely attempted (SOTV and SE are obvious examples), make them more appealing. Maybe give a bonus 10,000 XP for completing them - the code is already there to do that, Lost Skull pays an XP bonus for clicking on buildings but only if the adventure is completed.
Conversely, reduce the loot for popular adventures like IOTP.
Another easy measure is the cost in the Trade Office. When people can't sell SOTV for 1 fish, but IOTP sells for 300+ gc and Nords for 1600+ gc, it's obvious there's a problem. A developer or designer put in the effort to build the adventure, wouldn't it be nice to see people actually playing it?
Sure, weight some adventures towards XP gains and others towards loot, but make it worthwhile doing them all.