Lvl 41 expedition rifle is already arguably better than the lvl 36 mythic staff.

Arcane staff? Lvl 36 arcane = lvl 46 legendary
Lvl 41 mythic = lvl 46 legendary

Equal level guns greatly out-damage staves.

The arcane staff has lame procs and such.
New mythic proc sounds beyond godly.

Bye, bye arcane staff. Hello insanely priced new mythic gun!

Mages might have 700 damage even without the arcane ring... *drool*