I totally agree with you! We were very focused on finishing something playable (bcs we've never had finished anything before in a Jam), so we took the easy path, a 2-player game so the game logic would be the simpliest. But we received a few feedbacks similar to your, including one asking us for a single player mode versus IA. But it would be impossible in a two-day Jam.
Thank you so much for your feedback it's very constructive and much appreciated.