This has probably already been shared in here, but this is a pretty interesting proof of concept for an alternate take on the destruction of Alderaan. Minus the shot of Yoda I think it does manage to hit a much more emotional chord than the original did.

http://www.youtube.com/watch?v=6R1hgShD1IY&feature=related

If there was a way to actually make this work without having to recycle footage from another SW movie, it might be an interesting idea to play around with for a re-revisited cut of Episode IV. I definitely got the chills seeing people running and hearing their screams as their planet starts breaking apart. Maybe a new effects shot for the planet's explosion would make it more dramatic too, like if we can see the crust cracking from space, have a cut to Leia like in the video above, and then see it all blow apart? The actual destruction footage would be a bit trickier to get ahold of, but it's possible that some cleverly disguised footage from other movies as well as some second unit / new CG / matte shots could do the trick.