There wouldn't be much to change in terms of dialogue.

I suggested changing "There are too many of them!" to "Now there are two of them!"

And yes the would be less to explode but the added debris could look interesting and add chaos to lead up to the bigger bang to come.

It would also give Luke enough time to get to the shuttle and say goodbye to dad if the Emperor's station is falling apart rather than blowing up.

Remember the Rebels don't know about this one so no need to change the briefing or any of Ackbar's lines.

"We can't repel firepower of that magnitude!" can apply as much to one Death Star as two, maybe even more so.