Mmm...you could stand to lose some Amethyst Pillars in favor of Pendulums from the same element; if you either don't draw those Devourer or they get killed somehow, then you're going to get stuck with a bunch of
cards in your hands that can't be played for a while. The idea's good, it just needs a bit of quanta balance; Butterfly Effect + Devourer is still one of my favorite combos in the game.