Based on this post, the best path for raiders is to always kill Fyrakk on Heroic (or Mythic) each week, as well as killing every other boss on at least Heroic or higher for shots at the smaller bonus.
Based on this post, the best path for raiders is to always kill Fyrakk on Heroic (or Mythic) each week, as well as killing every other boss on at least Heroic or higher for shots at the smaller bonus.