I think there may be many people you equate Jade being infatuated with Ed with Jade being stupid, and that flaw colours their perception of her as so much time and narrative was devoted to that story.
History is full of amazing men and women, some brilliant, whose only weak spots were in matters of the heart. Who a person falls for has nothing to do with intelligence. Ed was Jade's blind spot (actively encouraged by Tully, Tim, the Sugar Sisters and Mikkayla), but she was perceptive, thoughtful and strategic in most other ways. She isn't academic, but she is smart