Pretty cool idea, but I don't think the online system works well for game jams. I also noticed that the movement was quite slippery, making it hard to do precise movement.
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We might have different ideas of working well ;) I agree it's pretty bad at getting many meaningful ratings because it's hard to rate without bringing friends or getting lucky with a random other player. But the again I learned how to do multiplayer with real world project, tried out some other ideas and got a better understanding of the engine all while having fun doing it and getting a lot of feedback.
Might not work to get a good ranking or the most plays but it worked well enough for me ;)