Another idea of TROS I had would be to remove the Death Star lasers from all the Star Destroyers in the Sith fleet, as well as them destroying Kijimi.
Though I have to admit, the planet blowing up is a really good looking effect. I think it would be cool to replace the destruction of Hosnian Prime with that shot of Kijimi blowing up, if a trilogy edit cut the Star Destroyer lasers but kept Starkiller Base.