NEEDED - Put a safe-zone/energy wall around the exit elevator. Players who make it to the exit shouldn't have to be fighting to survive against Phantoms while Herp McDerp runs around trying to find hidden boxes.
Optionally, I think it would be a nice idea to reward players for making it to the exit quickly. At the moment the Graveyard levels seem to be mostly about just running to the end and not getting much, if any reward for the stage. I know there are chances to get rewards by going off the beaten path/killing zombies and I like that risk-reward mechanic, but fundamentally the Graveyard stages are a "survival race" minigame, so rewarding players for working quickly would be nice.
are you kidding? graveyards are great for loot, is the phantom that hard to hold off? I do get your issue about waiting at the elevator safely though.