There could be a couple of guns added to Owen and Beru's skeletons to imply they shot first too.

We could gets glimpses of Jar-Jar on the Lars farm suggesting he is being held there as a hostage or a slave (Tatooinian Gothic). So when Luke is tearing up over the death of his adoptive parents the scene could be wrecked by the Gungan calling out. "Weesa Free!!!"

When someone dies Luke could suddenly change all his plans to be like his father in some way.

When Owen and Beru die he says "There's nothing here for me now, I want to learn the ways of the Force and become a Jedi like my father."

When Ben dies he could say to Leia (and it doesn't really matter if the dub is off) "There's nothing here for me now, I want to join the Rebellion against the Empire and become a pilot like my father."

Hopefully with enough 'Mark' material this could be extended all the way into ROTR with increasingly more bizarre combinations.