I think the whole brother sister thing was done wrong...
I did a rough cut of ROTJ and I based the edit off of this plot line somewhat.
Luke does not need to tell Leia she is his sister to protect her. As Ben told him to do so. (That is important I think)
When Leia get's shot in the arm I put this against the scene where Vader senses that Luke has a sister (preferably cutting Leia killing the storm troopers while Han says "I Love you" and Leia says "I know")
I cut all the Jealousy out between Han and Leia
And I tried to use the scene where he does reveal that she is his sister at the party as they are both still wearing the same clothes and makes it plausible. Although it cut's off short and feels like there needs to be more.
But I altered the dialogue of Luke "The force run's strong in my family.... I have it... and my Sister has it" Because Vader has now gone, the father of them both.
If only I could have added Luke saying "I was right" that would be what was needed to top it off and Leia nodding. or something along those lines.