What was wrong with just sticking to "bring my shuttle"?
This is ever so small, but one of the main reasons I hated some of the changes Lucas made. "Bring my shuttle" was said so curtly, you could tell he was fuming after what had just happened. Either angry, sad, just annoyed. Adding the clunky line about alerting his Star Destroyer just again ruined a moment. It was the moment ruining that annoyed me most.
Same goes for the added 'NNOOOOOOOOOO!' as he throws the Emperor. His silent contemplation was the thing that made that whole scene so memorable. He is a mask Vader. And to show the turmoil in him by just focussing on the mask, and his back and forth looks, the music and the direction did the job. There was no need to add a ridiculous 'NNNOOOOO!' at that moment ... it was such a shame that fans (not all, but some!) ended up knowing what made the SW films great more than the man who created them.
I know Simon Pegg hated that addition, and to be fair, I was an apologist for the special editions, but after that was added to the Bluray, I wanted the originals more than ever.