Your idea certainly has merit and I know a few posters here would like to see the second Death Star incorporated into ESBR, but I'm not of that ilk. I am very much pro-keeping each DS in their respective films. I don't think the 'skeletal' DS should even be in ROTS. In the shot as is (In ROTS) there's no real perspective as to what Vader/Palpatine are even looking at so to me it serves no real purpose to even be included aside from a ham-fisted attempt to bridge III and IV. Once ANH rolls around, the viewer could put one and one together to get two, but the DS was already alluded to in AOTC and that seems enough to me.
As far as incorporation of DSII into ESB, I think it'd be more of the same unnecessary FX and introduction of a new weapon best left to the movie in which it's actually used. I do like allusion in general in serials such as Star Wars, but limited to off-hand comments by characters which we then get to actually see in a future chapter.
Skipping to ROTJ, the audience gets a nice reveal of a new, partially completed DS in the opening scene after being told of its existence in the opening crawl. After seeing what the first DS could do in ANH, the viewer can sense a definite ominous presence to the new DS. I would actually like to see a more elaborate reveal of the Death Star II in ROTJ to give it a bigger sense of scale. I don't know how this would be possible, but it's one of the things that I think could be done better in the film (that and the horrible explosion of Executor into the DSII's surface at the end. Could that shot look more like a model and not a frickin' huge spaceship?).
I'm also not a huge fan of post-credits bonus scenes. If the shot's integral to the story, leave it in the film. If it's not, leave it on the cutting room floor or in the deleted scenes section of the DVD.
But, to each his own. My taste for film as well as my taste for Star Wars continually changes and who knows how I'll feel about all this years from now.
Good ideas, though. This is what makes the ot.com such a great place to hear others' views and get their input on what they like, hate, or want to see in the films we love. It's also why it's impossible to please everyone since our tastes can vary so much.