My advice concerning Bloodletter is with total group DPS in mind. With more than two archers in a group, staggering Bloodletters is a hugely inefficient way to go about the combo process, especially because every single archer needs to be riding every single cooldown in order to maximize personal DPS. And total group DPS is the sum of individual archers' DPS.
Right now on moogle our best archer is consistently peaking at around 100 DPS at the end of phase 1. Every archer should be pushing themselves to maximize individual performance in order to provide the most benefit to the group.
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Missing Keen Flurry on the list was definitely an oversight. I also changed the weapon recommendation to accommodate the changes to HQ structure and added -enmity as a possible materia choice.