The only reason Karen isn't killed early on even when she poses little threat is that Wesley wants her. When he captures her, he tells her this and where that goes- either Wesley taking her back to his apartment or Karen grabbing the gun and turning the tables- is up to you. (I would prefer no character death but *shrugs*)

+100 if Karen decides to play it out to try and gather more intel
+1000 if Wesley knows and takes advantage of this