The order of Polish if you have free time on the next jam.
1 - Audio, is the most important polish you can have if your game already have decent mechanics.
2 - Feedback : All the things you do should give player usefull information : Just look at all the interactions on detail and provide feedback to the player all the time.
3 -Tutorial : Is the way to engage the player into the game and show him the basic mechanics... dont think about a huge tutorial you culd just crete a waiting room to test all controls and then start the game.
Short game with constant feedback and game feel > Huge game full of content and no propuse.
A game is a succession of small meaningful choices