I like the pace and hectic nature of the game. Being able to lose multiple checkpoints adds to the tension.
I didn't find the watches very helpful. You go back so far that you might as well be dying and going back to a checkpoint. And I didn't find using the cheese very intuitive; more visual feedback on its range would have been nice.
Sound effects for picking things up and the hazards would really add to the polish.
A tracker for far you've made it would have been nice. Its fun to see how far you can get regardless of the emeralds.