I’m mainly going to go with things that can’t be easily fan-edited, rather things that’d require rewriting and filming

TPM: Make Anakin’s slave life appear more abusive and miserable, and show he has more trauma from it
AOTC: Include an opening scene with Anakin and Obi-Wan on a mission showing their normal friendlier relationship before it becomes more tenuous (because Anakin’s nervous due to meeting Padme for the first time in 10 years)
ROTS: Include parts from the novelization that emphasize Anakin’s stress and sleep deprivation (due to his nightmares) and Palpatine’s political manipulation of him
ANH: Vader’s in charge from the start and his portrayal is exactly like ESB; every Imperial officer but Tarkin is terrified of him
ESB: No Luke and Leia kiss
ROTJ: Add a scene before Vader defies the Emperor’s orders and goes to his throne room where Vader has a brief fight with the red royal guards; he easily force chokes them and tosses them aside