@ELPerro I agree, something like an animal headdress would fit a Shaman Archetype, however, they have not introduced a Shaman Archetype yet. Shamans would have specific magical power sets, that would probably be spells usable in Medium Armor, as Shamans would wear Hides and Headdresses more than any kind of cloth typically anyway.
As to the Wolf's Head giving a Dex bonus, any stat bonuses are thought to be animal spirit-related mystical bonuses, and thus defy the logic of the gear they are on. Otherwise, why would you get an Intelligence bonus just for wearing a Stag head?
Eventually, the game may add in some more Archetypes for the game, shoot, they only added the Archer and the Cutthroat recently, before that, we only had Barbarians and Arcanists (which would be more scholastic mages, not clerica/druidic/shamanic)
I expect, if they add in a Shaman Archetype (and mayhaps that will come when the promised Bard Archetype is introduced) they will start with some "heal other" type base spells, some Buffs, and even some kind of partial wild-shape ability, like Bear Claws, as well as having some kind of Spell Channeling weapon added that is more Fetish-related than a magical staff or wand.
