Here's a thought for you, a bit radical but see what you think.
Just about every culture has a myth of powerful creatures who, in times past came from somewhere to show them how to live in a better way. All these “Helpers” suddenly left, promising to return. Some sailed away, some ascended into the sky but they all had the same message, “I/We will return”. Now consider the Mayan calendar, promising the end of a cycle of over 5000 years this December. Now a lot of people think this means the end of the world, well what if it actually means the time for the end of the way things are done now, and what if these people are on the way back.
Just suppose, its December 21st and the sky is filled by an alien craft, creatures emerge and say, “We told you we were coming back, what have you done with the gifts we gave you, the knowledge we passed on, are you all living in harmony with your world”?. Will there be a stunned silence?
It’s a bit like the exam question for prospective masters of the universe,
“If we fill a planet with the most diverse range of plants and animals, and with all the natural resources for living so that no-one needs to want or live in fear, which species would be best to look after it, Humans or Dolphins - Discuss with reasoning”