Thanks guys. Very interesting suggestions.
Ronster: the idea of cutting between Luke and Leia when Leia gets wounded is excellent. Trouble is that in my edit she's shot by Fett not a stormtrooper, and the way the scene has been re-edited I doubt cutting to Luke would work in that moment.
I definitely don't want to use the Obi Wan scene. I like how the opening ten minutes flow right now, and a long sit down to explain everything would kill the pace. If I had better skills at After Effects then maybe I could add the Obi Wan scene to the Ewok village before Luke surrenders, but I honestly like the idea of Luke using the Force to figure out who Leia is. It's just a question of whether the audience will keep up, or wonder if they've missed something.
Bingowings: I like it the idea of the audience getting the information incrementally. "another Skywalker" "it's you, Leia", "especially for... sister".
I'll give it a try, although I suspect the audio editing will be a problem. (it might be one of those situations where that Adobe software that's hopefully gonna be out next year will be required)
Thejediknighthusezni:I agree it should be a big moment in the movie, and it's really a shame how they botched it. I quite like the movie without the subplot, but unfortunately it ruins a key moment: when Vader is baiting Luke and Luke finally attacks. It's too important a moment, so I'll have to put the subplot back in.