Maybe reimagine Starkiller Base as a Star Forge. That would explain how the First Order got so strong. Hux’s speech would mark when the first dreadnought built by the forge hyperspaces to Hosnian and uses mini Death Star tech to destroy the Senate.
I’d keep the restructured approach. Not once did I think D’Qar was in any danger. It’s just instead of a superweapon being launched against the Republic, it’s a fleet of dreadnoughts.