Don't know if this helps, but I usually do this. If a tank ever used the countdown, at least 7 sec. left or test it out on a dummy.

Quelling>Raging>BfB>Hawk>IR, Straight. By that time the tank pulls...cont. Venom>Wind or vice versa> Barrage>Empyrean.

That's how I usually opens. The buffs and crit hit rate will increase the dmg on your DoT, but also the barrage>Empy combo. I doubt you'll lose the buffs while doing it.