I would love to write and produce a feature set 14,000 years ago. The actors would not speak a language but would use gibberish and sign language to communicate. The up side of this is certainly low production costs. The downside it would need SE for the animals in the story. The story would be (basically) a young woman (A cave painter) becomes the head of a clan of people and must guide her clan through the perils of living in those prehistoric times. She doesn't do this like a supper hero (So tired of those movies) and bust heads but uses her smarts to succeed. The last movie set in this time period was Quest for Fire in the early 80s. Time has come today.