One other thing I’ve mentioned before is that during the Space Battle of Endor (and possibly during the Ground Battle) there should heavy casualties from both the Empire and the Rebel fleet afterwards, not just a majority of the Rebel pilots surviving afterwards and most of the Empire fleet being destroyed for a happy ending.

For example: in ANH there were many heavy casualties to Red Squadron during the Battle of Yavin to where only Luke, Wedge and a single Y-Wing pilot were the only ones who made it in the end (plus the MF) and not a majority of the Red Squadron pilots surviving afterwards for a happier ending.