Honestly, I doubt you'll see any new content, or major changes, they sort of already offered a "Complete Edition" because they have/had a preorder/purchase bundle that is the base game plus PL, which was even on sale at one point during preorder, so it was both for like $60,
IF they do put out an official or separate GOTY/Complete/Ultimate edition. I'd assume anything they add as bonus content would be pretty small, something like a new car, a unique cosmetic item/outfit, and maybe one or 2 side gigs, just to add a little something.
Having said that knowing that TW3 got a next gen upgrade years after release and it added a significant amount of content and changes, IF they really go all out on a special edition of some sort things I'd like to see considered are:
1. New apartment or House,
2. More immersive side interactions, similar to what mods have added, have a drink with a friend, actually have interactions with partner not just the same 3 dialogue options after you get the key to their apartment, things like that.
3. A decently interesting side quest chain, like 3-5 small scale missions that all tell one story. Maybe an interesting new character, or something that references the larger CP world (Edgerunners, Tabletop Games, Books Etc...)
4. Better Mod integration, on console I know it's never gonna be full mod support, but maybe add some optional mods/features/settings like they did with TW3 next gen update.
5. Functional Metro/Cab/AV system, more dense/realistic pedestrians something a bit more interesting than just fast travel points. The lore supports it so it just about implementation. Just overall making the city a bit more alive, Maybe even opening up some businesses for some simple interactions like bar/clubs/stores....
6. Brain Dances that are just for entertainment, honestly could be just a few short funny 3-5 min clips, or a short anime, anything that isn't directly mission related. I'm sure some people would want more "Adult" BDs, but I'd personally be happy with just anything that adds a bit of flavor or lore.
Those would be my top list, and for what it's worth I would still expect the other more "Realistic expectations" I had listed above, I'd expect them way before the rest of my list, but my list would be a really nice bonus. But knowing they're going to be opening 2 new studios/offices and working on at least 1 Witcher game and CP Orion simultaneously, as well as any other projects going on, I doubt we'll see much more work on CP2077.