Well, if I ever do get to try it, here are my initial thoughts:

Remove 49 minutes from the Maple Films Hobbit edit

Begin with the Maple Films version, trimming further as inspired by the 3hr Spence edit and 2hr Fiona Van Dahl cut.

Loose ideas

Include visual montage of backstory during the fireside song
Remove pocket handkerchief gag in favor of beginning the traveling montage
Dwarves go along with “they’re infected” right away
Probably remove Gandalf and Elrond conversation at night setting up white council and dragon sickness
Mute Thorin saying Bilbo has no place amongst them
Experiment with reintroducing the flashback that introduces Azog
Perhaps include the EE two-by-two Beorn scene
Trim Gimli reference and Bilbo versus baby spider
They don’t get into fish barrels, just show up already in them
Cut down the Master and Alfrid more, but be mindful not to go too far
The dwarves do not enter the mountain before Smaug exits
Bard shouldn’t go to jail and can just spring into action
Search the subtitles for ‘dragon sickness’ to kill all but the briefest allusions to the idea
Maybe don’t even show Bilbo leave and give the arkenstone away, letting it be revealed to us as it is to Thorin
Add a subtitle comma to the Azog line that was missing one