If I had my own way I would add cues from the OT to the PT not the other way around.

I'd make the Imperial Cue from ANH the Stormtrooper/Clonetrooper motif so if the films are seen in sequence the blockade runner scenes resonate with the sequences with Clonetrooper action in the PT (it's a nice little motif which was kicked into touch by the Imperial March which shouldn't have been used in the PT until the final moments of ROTS).

I'd have put hints of the Luke and Leia theme into Padme's talk of pregnancy and then not revisited it until we know about their blood ties in ROTJ.

Sticking PT stuff into the OT, if ever done should be done sparingly to make a story point (I don't mind the PT music in ANH:R because the final confrontation between Vader and Obi-Wan is an echo of their PT fight but there aren't that many instances in the OT).

I would love to see some of the missing score of ESB put back if it's possible and if it works, though sometimes the score changes do make sense.

Vader confronting Luke without the scored music is much more powerful than the same scene with the music put back.