Which focuses more on unlimited power?
I would say both in their own way. The sorc definitely fits the story line better. However, I could see both assassin and sorc striving for the "ultimate" power each in their own way. The assassin would want to further his power in the force by learning new force techniques to disable and deceive his foes, and focusing on his martial prowess at the same time. The sorcerer would definitely want to search for ancient text and rituals and hidden places of power.