Anyway. The Quickshot buff is definitely a very good improvement for demon EAs, but the fact that it stacks with demon spark is inconvenient and indeed a little too much, considering the new G19 arrows they have. But I can imagine that it's actually the arrows that make the greater difference when using spark due to all the attack levels they got, not the new buff.
Edit: Although demon sparking archer is not something you see often, so it's not a big deal.
Just my 2 cents~