In response to hollowsgrief, the Empyrean Weapon Skills are most of the reason that most Empyrean Weapons (and, quite absurdly, most of their Walk of Echoes counterparts) outperform Relic Weapons. In other words, if your Empyrean Weapon Skill sucks, then in all likelihood, so does your Empyrean Weapon. Because of this, there is a shining exception to the rule of Empyrean superiority, and that's for Mjollnir still being the best damage-dealing Club in the game. Which is great for the melee White Mages that got it! But hardly consoling for everybody else.

(Strictly speaking this also means that the Hvergelmir is even worse than the Claustrum . . . but at least the former isn't as much of a pain to get.)