I am really enjoying GW2, especially WvW.
Any chance of being able to play as a monster/boss someday? (I HATE scripted boss fights)
If you want truly dynamic events, have players control the monsters (you could still have bots fill in the gaps). I would absolutely love to chase people around killing everything in sight until enough people show up to kill me. You could have a separate leveling system for monsters all the way up to the dragons or whatever.
This is something I first thought about during my WoW days. Raids always felt more like puzzles than a true fight.