Unfortunately gse no longer works as well as before until legion, the blizzard to changed several things in the lua and macro.
and in fact today CDs can no longer be put in keypress . spell are never used instantly outside coldow and often rotations with castsequence are wrong.
as you say you flock of crows as well as the other spells are also used with 5 -6 seconds delay. for example I use both aspect of wild and I beat lwrath manually while for barbed shot my personal macro performs it discreetly.