This sounds good. I think you could at least play around with starting the film with Kylo already on his way to Exegol. Either starting with the shot of Kylo’s ship flying to the edge of the nebula, or pan down to the nebula as Kylo jumps out of it and flies towards the surface of Exegol.
The fact that we don’t have any extra deleted scenes of Mustafar, or the fact it doesn’t even look like Mustafar, makes me lean toward just removing it and allows the film to not start on an action scene for a change.
I was really hoping we’d get the Hux/Pryde and Oracle scenes for Mustafar to flesh out that section (so that you could hypothetically push Exegol and Palpatine to later on as in earlier cuts of the film). Now I’m not quite sure what to do. I’m reticent to cut too much out of a film that already feels cut to the bone, and especially in a sequence that feels particularly that way. I also feel like they didn’t really want to start with an action scene either, so that’s why we get this sort of montage-y bit (that in my mind gives the sensation of a larger montage where we see him searching and conquering other planets that we just don’t see) where it’s not really about the action. I fear just starting out the film on Exegol because Palpatine’s entrance is such a big whammy you really need to build up to it (plus finding Exegol is the plot of the movie so I think it needs to seem somewhat challenging to get to). That’s why putting him in the crawl feels so weird. Now that I think about it I almost wonder if there needs to be a more overt tease in the crawl like saying “dark secret” or some such.
Personally I don’t really mind that it doesn’t look like Mustafar, just because it’s not mentioned at all, so it almost doesn’t matter. I keep trying to think of a way to just start the movie with Kylo on the bridge of a star destroyer (from the TLJ deleted scenes), then someone says off camera his ship is ready, then we see his TIE flying to Vader’s castle (using RO footage). My problem is, besides the tough VFX work, what happens once he gets there? Ideally you’d just have him go in and take the wayfinder, but when he gets the wayfinder in TROS he’s outside and all dirty and shit, so that footage wouldn’t work.