Canonically, ROTJ takes place 1 year after ESB, so if you show the DS in it, I suggest doing so as an "epilogue" (think the epilogue that was created for the Darth Editous/ADM Hybrid edit of ANH) after the credits.

THAT would be cool, and would allow more freedom without making it all seem the same.

See, I was a bit worried with the Prequel music and Imperial march being added into ANH that we'd start to get sick of this stuff because it would all be in every movie now, instead of us experiencing more and new things as the episodes progress.