I've downloaded and watched the Spence final edit now. It's definitely an interesting edit with a lot of unique ideas. I especially like the re-ordered opening with Degobah. Alas, as much as I admire the intent behind this edit and the technical execution, it just doesn't work for me.
I find a number of the cuts make the film feel rushed, especially in the Jabba the Hutt sequence. I understood the attempt that was being made with the intercutting between Jabba's palace and Degobah to make it seem like Luke was sensing what was happening with his friends, but it's so unlike any other cuts in the rest of the Saga that it just feels out of place to me. I like the idea very much, I just don't feel it was successfully acheived.
I appreciated the trimming of Han Solo's funny bone, and in places I found myself thinking I'd have gone further with those trims. I also really like the idea of having the Emperor on the Super Star Destroyer. However, I just don't think it really works. The view from the Emperor's window seems to be on the other side of the DSII from the space battle right up until the rebels attack the SSD, at which point it's suddenly in the thick of the battle.
The death of Anakin has some audio issues. The ambient hum of the death star disappears a lot. I get why the new music was inserted in this scene, but since the original music was married to the sound fx it becomes obvious everytime the original soundtrack has been replaced as the sound fx disappear.
It was an ambitious edit and it's definitely an interesting addition to my Star Wars collection, but it won't be replacing the original for ne as I'd hoped it might.
PS. I noticed an audio issue in the transition from the opening with Vader to Degobah, I could clearly hear a few notes of the Tattooine music from the original artoo and threepio scene. Just mentioning because I know you're going back and tidying up some of those editing gaffs.