At one point, Harmy was actually thinking three different color grades for 3.0. But that was back when he had a weensy more free time. Now I think this is his plan:
For v3.0, I’m actually planning on using Neverar Great’s corrections - we have been cooperating behind the scenes for quite some time and his results are amazing. He’s currently matching the BD to the I.B. reference with unbelievable accuracy and then I will probably use that as a basis and do something very similar to what Towne32 shows above, in eliminating some of the I.B. Print’s color biases.
So basically if this is still true, 3.0 will have the same IB Tech print target as it has now, but more accurate to the references we have, and without some of the oddities of the IB Tech prints. I doubt that’s going to do much with the brightness on Tatooine, but the Despecialized Star Wars is showing its age more than the other two films, and I imagine it will still be quite a pleasant improvement.
There are lots of reasons for the differences you see between 4K77 and DeEd. Optical duplication tends to increase contrast with every generation, so projection prints have higher contrast than whatever higher-up source was used for the Blu-rays. So the projection prints have print fade, less detail and more contrast, but the Blu-rays have more detail, less contrast, and all sorts of nasty inexplicable color issues (plus stupid dinosaurs in Mos Eisley). They’re really coming at the problem from two very different starting points, and expecting them to meet at some sweet spot in the middle may be expecting too much.