warped trench
This one is simple. Last year, people just REFUSED to actually tag people in monster mode. This kinda defeats the point of monster mode. I think, to fix this, if a monster has remained unchanged for 5 minutes, the monster will die, and enter spectator mode. This is a mode where you cannot interact with ANYTHING. This makes it so there is actually a punishment for hoarding monster. This fixes the main problem with monster mode, and I think its the best way to do so. When you enter spectator mode, the monster gets applied to a random person.
rigid pier
orchid jolt