Shaw, having Hayden there is just another one of the totally unnecessary additions that George put into the films. Seeing Yoda and Obi-Wan, next to a young Anakin just doesn't mesh well with the scene at all.
As for having our cake and eating it too, one person (I can't remember where) suggested a compromise.
Show the three Force Ghosts (or Jedi Spirits, whatever you want to call 'em) as they are in ROTJ for the normal duration, and then have them slowly fade into "younger" versions of themselves. Shaw becomes Christiansen, Guiness becomes McGregor and finally ol' Yoda puppet becomes CG Yoda in his prime like we've never seen before... at a spry 100 years of age, or something.
This could show the characters as they were when they REALLY died, all as old men, and their "rejuvination" in the Force to show that age no longer has any meaning for them. Luke smiles, rest of movie continues as before.
I like that idea. Ever though of suggesting it to George Lucas?