The impact of reducing curation rewards isn't completely unknown, since previously they were 50% less for several years.

But after reading some of the other suggestions here, I think it might be more interesting to focus on changing the curation window code and reward process for very quick voting, as that seems to be the dominant thing that gives such an advantage to auto-voters over human curators. Unfortunately, that's probably slightly more work than a simple parameter change, but my gut feeling is it's probably not that difficult. As soon as we get thru though hardfork, I'm going to have someone look into that section of the code and see just how much work would be involved.