Hex: D. The additional hit is far worse than many of the other skills that could potentially be in the slot. The least of which is Anathema.
Anathema: C. If this were any other Fire Emblem, this would be an easy B, if not A. In this game, however, having a bunch of units next to each other (let alone *enemy* units) isn't likely outside of choke points, and there are better choices in those cases. As this game is based heavily on spacing out units, it's extremely unlikely to get more use out of this than any other generic +Crit chance ability (the + to hit is completely irrelevant). Depressingly, this skill is one of the more overrated skills, when it really should be one of the best ones. Sadly, this game just doesn't want it.
"A shouted order to do something of dubious morality with an unpredictable outcome? Thweeet!" My FC is in my profile.
Hex: D. I hardly found this skill useful with Dark Mages since I only attack in range unless the enemy has range too.
Anathema: B. Underrated, as people have said. It reaches as much as a Rally, and not only does it makes you hit more, it adds crit. Easily one of the better Base Class skills along with Vantage, Movement +1, Gamble, Armsthrift and maybe some others.
In the name of the Fang, I sentence you to death. Daily life of Galeforce boys: http://i.imgur.com/BPlqiom.png