My crossbow does 52-111 base damage. I've only recently seen a bow that did comparable damage to a crossbow (not as good as Kiya's). If the damage improves for bows, I would probably switch in a new game.
I try to avoid having my DK run around as a distraction, but needed to do so for a couple of the blood knights around the temple in act 3. I would run away to give him enough time to cast a healing spell then attack again, or run around if the blood knight was just about dead and I didn't want to use a potion for the DK.
After fighting an air elemental and 2 blood knights (separately) north of the temple, I headed towards the wall to gather loot, when I heard my hero start firing arrows. I quickly healed and started running north... to find some loot and a spell book from the now dead mage Looc (checked the trophy list to get the name).
My characters were both melee for much of act 1. This worked well for melee opponents, but not that great for ones that attack from a distance or frequently run away. If I was continually chasing someone, they were the ones controlling the fight, at least until they ran out of stamina.
