Thanks for the suggestions!

It's a pleasure!

Another "trick arrow" idea might be, similar to the gas arrow, a "repellant arrow": an arrow that acts much like a smoke bomb on contact, but that instead of releasing obscuring smoke, releases a cloud composed of a mixture of silver dust, garlic dust and vaporised holy water: a sort of nigh-universal monster-repellant. It might be useful as a crowd-control utility.