I think this skill is fairly good at the moment. Its five seconds of projectile negation on a twenty five second cool down, and a water field, which makes for excellent synergy with Ancestral Grace. It is also the kitten when it comes to stomping revenants.
But at the same time I feel like its just a little too niche at the moment, since not all classes use projectile attacks that often. So, what if this skill granted a small bonus to allies passing through the field, like protection for a few seconds, and then gave enemies a condition as well, like weakness. For one, I think that would fit the name of the skill of excellently. Secondly, it would give it some better utility when up against a foe not using projectiles.
Stormbluff Isle