I Ike it! I think it works better as an almost blinding light rather a very clear, properly exposed explosion. I did notice some flickering on the bottom a little.
The flickering is from an encoding issue, otherwise, the only thing left is the debris of what remains of Alderaan.
I would try some rubble over laying some of the blast, with a glow coming from behind it that will do a light wrap. So we get the effect of rubble coming toward us. If you check out my Prequels Revised Trailer 1 or 2 there is a shot im creating where a building blows up. Its still in production and not done but something akin to that.