I know that video feels that the viewer need literally no build-up to Vader appearing in the hallway, but I disagree, even if every single viewer is already familiar with him.

I like your list of changes otherwise, but I would suggest leaving mentions of Vader in dialogue throughout and his arrival at the end of the battle. I’d consider using the first chunk of the Mustafar scene (minus line about Krennic arriving) to depict informing him about the battle as Tarkin orders (ending with Vader getting out of his bath).
You’d have all the good Vader stuff, a cool introduction and in-character moment prior to his “I’m a fucking badass” scene. I have a hard time imagining it feeling right to literally only see or hear about Vader in that scene.

And if you remove the floppy disk being handed down the line, you lose the tension of that scene, right? Other than these things your edit sounds great to me.