What if Fiddle's Crow damage started low but increased with the repeated bounces on the same target?
Instead of it always doing, let's say (for the sake of explanation) 100 damage on each bounce including the AP scaling (= 200 total with 2 bounces, 300 total with the max number of possible bounces), it could do 50 the first time it damages you, 250 total if he manages to get 2 bounces off on you, and 600 total if he manages to get the max number of possible bounces off on you.
This way his ranged harass would be much much weaker, but as a tradeoff he'd get much better dueling/all in power.