I think the time is fine at 15 minutes, but there should be some sort of score cap to stop steamrolling games.
I suggest paying attention to the next week or so and looking back at older weeks and seeing where the scores are in regards to close games and runaway games. If then there was some way to have a score so high, that if both teams were even, it would be practically impossible to get to, but low enough that a runaway team would reach it and end the game early, that would be best.
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