Well, also the upgrades and the AI-controlled snakes. My original vision was more about min-maxing your position in the polls, but I toned that down because I didn't think it would appeal to people as much.
But yeah, for me game jams are about working on mechanics that are new-to-me, rather than trying to come up with completely original ideas. I was really interested in working on the mechanics of the snake, and that was what motivated me to give up an entire weekend making a game 6 people will play.