Just level up the essences and the skill and voilà ...
You can optimise with self supported essences but not required.
at hight level the cooldown reduction given with one attack is enought to relauch ice shield. directly so just spam it and watch the world burn from your arrows.
The attack speed is just here to easify the attack between ice shield launch.
Work with any characters, melee or distant, personnaly i prefer melee traveler to have the damage area from the the ice shield.