I think I know a way to keep the Hux speech.
Instead of Hux witnessing the first firing of the weapon it is when it begins to suck the star. When he says “Today is the day…blah blah gets destroyed” it would still work because it’s just later in that same day the republic gets destroyed. You would remove him saying “Fire” and replace the shots of it actually shooting with some still epic shots of it sucking up a star shown later in the film. You would then cut all dialogue mentioning destruction of Hosnian system. Then put all shots of it firing after Hans death. This idea is from this amazing article. I suggest reading it all the way through and modeling it after this way so that you could keep Hux’s speech and move the destruction.
https://humaniterations.net/2016/03/26/how-to-fix-the-force-awakens/