[Ecclesiastes]

No, there's no need to raise dex for an AoE whatsoever, unless you're a Blade. The leveling will be a bit slow, but if you can get a hold of anything that raises atk speed, dex, or anything at all that will help kill your enemies faster, than go for it. I'd recommend a Sardine set, an atkspeed shield, and those lovely pang buffs.