The Elm Great Bow is a good weapon, but is very far from being the most dangerous one you'll encounter.
Not all Runes have the surge ability to "blast" but does that do really inconvenience the OL because it gives the heros serious crowd control.
I would suggest going over the purchase deck and looking at all the various weapons and armour and finding out how they can affect the game play.
One of the best example is the crossbow. It has a surge ability to move a creature one space. How does it work? Can you use it to reduce the range? Who decides where it moves? (For a surge, on a succesful hit move the target one space, even if it took no damage; you cannot use it to reduce range, it applies after the apply damage step; The hero decides where it moves to)
Edited by Alarmed