My curation rewards aren't any different from any other stakeholder who uses their voting power, relative to stake. Since the last few hard forks, curation rewards were made linear, except to the extent of downvotes or voting late (after 24 hours). It no longer adjusts in any meaningful or complex way to small differences in curation "performance" and has been turned into a participation reward for using your stake to direct rewards. Most stakeholders supported this (though, to be clear, I was a bit skeptical).