I think 24 hours is a bit tight, that's not really giving people chance to do anything, 48 hours I think would be enough, and like you said, if they go nowhere after that - next person can take a shot at it.
Alternatively, if people are getting itchy mouses, why not have a few on the go, and people can add to ones when they have time, or start their own for others to jump on to?
I'll give this one a crack now then...
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