No Double Teams
This may be the most important factor for the Colts. A defense can focus on Hilton and he will still get his numbers. But what happens if he has a receiver on his level opposite him? What this does is open the field more. Normally, if a defense is playing man against the Colts, they will leave a safety in space just in case Hilton breaks free. With Amari Cooper on the other side, they can no longer use a single safety. This will force a defense to play more zone.
What that will do is open up the running game for Marlon Mack. Stacking eight in the box has become a thing of the norm for defenses lately as most teams are not fortunate enough to have two top 10 receivers on the field. Mack and the offensive line will see better holes thanks to the respect that Cooper and Hilton will command in the passing game.