To say Sakurai bases his choices on reps based on story influence is wrong, Sakurai HAS said, however, that he looks for 'story-driven' characters, which can be reasonably interpreted as being driven bytheir story, i.e., their personality (which Sakurai imagines and injects into the characterless characters, see, R.O.B. and G&W and how they act in SSE), and we've also seen him say if HE thinks they can work in Smash (as in he can devise a moveset for them or likes them) then he'll put 'em in. There's certainly no real barrier for Anna that we know of for certain, only those manufactured by her detractors. (<- bold claim)