I wouldn't call Hak-Ju Lee an impact bat, but his all around game is enough to have a big impact. He could be a guy who hits 290-300 with a 350-360 OBP, steals an enormous amount bases and plays extremely strong defense at SS. Even after TJS he has a cannon for an arm and his range is huge. If the Cubs absolutely must keep Castro at SS then they could always move Lee to CF.