Like what? We got new storm troopers, new ships, new planets, new vehicles, new bases, new weapons, new characters.
I'd argue the only time the old cannibalizes the new is with Tarkin and Krennic. Seemed like they were afraid of making Krennic too powerful and intimidating of a villain because it might diminish Tarkin and Vader's presence/role.
I never felt this "encroaching" that supposedly happened in this film.
This is what I mean by the old overshadowing the new:
Forest Whittaker does nothing in this movie. He is just there to make the 10 viewers of Clone Wars nerd out. He literally just stands there, hits play on a USB stick, and dies in this movie. What would have been different if the pilot went straight to Cassian, a character that actually matters in the whole movie and we could have gotten further insight into? They still would have needed Jyn to verify the message.
The scene on Mustafar. I know TPS reports are important but this isn't office space and I don't need to see Krennic go weeping to Vader about office politics. What was the point of that even? To find out Vader has a butler? Lol. It didn't affect anything in the story at all.
Cut those two scenes (and others) and add actual scenes with the new characters. Maybe then I would have cared when Jyn and Cassian caught the worst sun burn ever.