Lemme see if I remember too much of these books. As I recall, (up to I think the Books of the South/return of the Black Company) we didn't see too much of the sorcerors doing anything, but I'm not sure if they've got as much power as a D&D wizard. Let's see...
Limper: Warmage/Incantatrix/War Mage (Age of Mortals). All he ever did was throw around giant nuke spells. Admittedly, this is considered a bigger feat in the setting than, say, illusions, but nuke spells suck.
Shapeshifter: Your build probably works fine, persisted shapechange. If we cared enough we could teach him the polymorph subschool too, but Shapechange is fine.
Soulcatcher: No frikkin idea, we haven't seen her actually throw down with magic to my knowledge.
I'd represent the process of Taking with the Necrotic Cyst feat line, or maybe the Programmed Amnesia spell (Mindrape is too fast, and the spell the Lady used took a lil bit). Other than this there doesn't seem to be any enchantment. Note also none of them get fly spells.
Honestly, the concept of the Taken were cool but they didn't get enough screen time for us to do this.
