That's amazing!!! At first I wasn't sure if I liked the actual idea of Sidious transforming before the duel (I've always liked seeing the calm and reserved Palpatine we'd known for two and a half films letting loose), but this is AMAZING!

Also, perhaps as soon as Anakin runs in when Mace has Sidious cornered, Sidious' face can revert back to normal so Anakin doesn't see him as a Sith as much. But as soon as Mace starts to piss Sidious off again ("You have lost"), the face could change back (especially if you're keeping the "No, no, you will die" line, which I've always liked as it's the moment, in the original version, when he lets out thousands of years of Sith frustration and hate in one line).

Thoughts?