If you want to make your enemy fly away you should play a monk.
Two Handed style is ok. With Firebrand it's nice because the base damage of that weapon is very high and thus works very well with damage bonuses - even if it's "only" 15%. As Priest you can add Savage Attack (+20%), Apprentice's Sneak Attack (+15%) and if you're a Priest of Skaen also an additional "baby" Sneak Attack (+20%). All in all that's an impressive damage bonus of 70%. With Firebrand that's pretty nice.