I have a somewhat silly suggestion. In Episode II, when Jango Fett is walking up the ramp into Slave I as it takes off, he bumps his head as he goes in. Rob Coleman says on the commentary that Jango was clumsy and that it was "cloned into the stormtroopers" (whatever that means) and that's why one of the troopers in the death star bumps his head in A New Hope, (I think you know the one I mean). It was just a way to explain away an error in A New Hope, but might it be neat if there was a somewhat muted Temura Morrison"aghh" when the trooper hits his head? Hmmm.