I love the vision of the game and the entire concept, but as good as the concept is and as ambitious as it is, this seems like a great challenge in scope for this team within this time constraint. With that said, I appreciate the honesty in admitting the progress in sprint #1 and the action taken in making changes to the production plan. As a personal suggestion, as this is a very big game, it would take a lot of time in 3d modeling (which has not been shown in the video) for the environment artist; maybe the team could consider creating a "tutorial level" of the big game for this game jam. This will put the team's focus on the details of a single level, making time for designers and artists to make a polished level instead of a gray-boxed and empty game. If you can surprise and attract the player's attention, even a 5-minute gameplay is worthy of doing.