As people are rightly pointing out, this is only ever going to be a crude heuristic since it has no idea of the context. But in that spirit, I suggest including

As people are rightly pointing out, this is only ever going to be a crude heuristic since it has no idea of the context. But in that spirit, I suggest including the distance between the notes as a factor. That would help with slash chords (E2 C4 G4 Bb4 -> C7/E because the E is much lower) and extensions (distinguishing a sus2 from an add9).