And very welcome two cents they are. I know exactly what you mean. I really hate to say it, but it seems the emotional detachment Lucas was lambasted for with the prequels is just as present in the original movie too. I mean, you're absolutely right; Leia's muted response to Alderaan being destroyed is really rather unsatisfactory. If you've heard the Radio Drama, you'll know what real pain should sound like with those wonderful scripts and performances.

However, as much as I find the emotional impact wanting, there is also the fact that Star Wars is a war movie, and the mentality of war and in the underground movements wasn't dissimilar to what we see. Loss was a daily occurrence, where anyone could disappear or die at any time, and you had to carry on regardless. As the exchange goes:

Rebel Commander: "When we heard about Alderaan, we feared the worst"

Leia: "We have no time for our sorrows, Commander."

So I can let it go with that perspective. But then, as you said Darth Plagueis, if I'm trying to imbue more emotional impact will it fit with the responses of the characters? Well, I guess we'll have to see. I must say I'm inclined to remove the planet surface shots, even if they work visually, as I like the momentum of the entire planet being obliterated by the shockwave uninterrupted.