It writes itself, but they need to be careful. Are you really going to have Rollins/Balor III in September? I can't think of a logical face for Balor to face for the belt however.
I think Drew has to go over Gunther for the IC title. That takes him away. Riddle? Meh. Orton could be something. Gable/Balor would burn the house down but that would be kind of random. Ciampa would be too soon. Nakamura would have been a natural for it with his history with Balor but it looks like they're turning him heel.
I think Balor turns face eventually when Priest turns on him eventually. Long term speaking, you can have Balor lose the belt at Mania via a cash in fron Priest after a war with Gunther (who won the Rumble), and move Imperium to Smackdown afterwards. Question is can they hold that tension for almost 8 months in the meantime?