I don't have many suggestions for ANH:R HD because I think Ady already has it covered in terms of how this will be so I think the blueprints are there if you like.
But something I would like to have seen was a brief inclusion of the emperor. And I think I found the spot. After Luke is doing his lightsabre training and they are coming up on Alderaan. We cut to the conference room.
I was wondering if we could have a brief glimpse of the emperor in this scene over a hologram in the center of the table and phasing out like the conversation has already taken place.
It's the scene where a guy walks in and says "scout ships have reached dontooine"
It's a small touch but it gives the impression of him as a shadowy figure working behind the scenes and no dialogue either.