The debuff-refreshing factor of Poison Touch has currently no feedback at all. Compare it to e.g. Silencer's Arcane curse, which has a visual effect indicating whenever its duration gets increased. Poison Touch should have some indicator as well. Dazzle currently has a tick sound for Poison Touch in the game files, but it's currently unused. A good use for it now would be to play it whenever the debuff duration gets refreshed.

This is the unused tick sound: poison_tick

Make this sound play for the debuffed unit whenever it gets the debuff refreshed on it. It should be loud enough to be noticable through the attacks' sounds, but not too loud to be annoying or overtoning other sounds.