Wouldn't a more simple concept be to set the rewards at 50/50 and curators who upvote content would split the 50% rewards based on the time you found content, with a trickle down affect with late voters getting the least? And I agree that vote bots should be eliminated entirely. The voting process should be manual.
On the leased curating if one is leasing SP they should have rules so they are NOT upvoting just their own content or their friends, they should be required to find so many new content upvotes to prevent the abuse from some who are leasing SP. When I'm looking for new content I agree with @blocktrades, I can determine if it's good content in about 5 minutes.