Shapeshifter sounds like an amazing Hybrid Mage. Giving her several forms, each form replaces the 4 abilities with 3 abilities and an ability to revert. 2 Forms seems appropriate, one primarily around being a Warrior Type (Bear) and one around being a Rogue (Spider). If we wanted the Morrigan special we could add in Insect Swarm (Mage).
Then for standard spells, make it a bit nature-like, like the old keeper, one with nature, thornblades etc.
Other concepts I'd like to see;
Primal Mage (Ice/Lightning/Earth).
Add in a major lightning field like Tempest from Origins and some earthy skills like Rock Armor/earthquake.
Force Mage
Some Crushing Prison, Fist of the Maker, Mind Blasting, Pull of the Abyss, Gravitic Ring sort of Action.
Hexing Mage
Poisoning AoE Spell, Miasma (Weaken/Shock/Chill, Damage over time), Death Hex (all hits on target are crit), Sleep (AoE Sleep), Waking Nightmare (As Origins)
Blood Mage
Blood Slave, Hemorrhage, Draining Aura, Blood Magic Toggle, Drain Life, etc etc.