#6 Finn Balor
Another person that will be positively affected by The Shield breaking up is Finn Balor, who became an afterthought in WWE when the faction reformed the night after SummerSlam. While Balor's ascension to the top will probably still be a very long one, opening up some slots at the top of the card will ultimately be beneficial for Balor
Of course, it's still a matter of who WWE will fill those slots with, but even if Ambrose doesn't get chosen for a top spot immediately, it will at least give him and other superstars more opportunities in the mid-card.
In the end, it may take a while for this to come into effect and will be dependent on who WWE chooses, but its a possibility that Balor climbs when The Shield splits.