Instead of just hitting the opponent, the Boomerang will home back to you for re-use but with slightly low durability. I would personally love it. (I'm suggesting this from my own playstyle so please don't hate on me.)
With my aggressive playstyle when using the Scythes, there are times when we lack the appropriate reach to hit the enemy, that's when the boomerang can give us the extra reach we may need or when someone low on health is trying to run away and it helps prevent that.
I'm not saying it should have really high damage, more like a supplemetary weapon that deals similar damage to the black firebombs. I feel that this would add slightly more flexibility in combat.
Then again, i'm speaking from a personal standpoint. What do you guys think?