I am with you on all you have said but try to look at it more in a sense of a sliding scale.
When you weigh up those shots that are particularly badly damaged exhibiting the "rusty red" saturation hues and the hyperspace cockpit view you get to a point of saying the video source is not viable. Because well let's be honest they are a write off for so many reasons they are for want of a better word "Shit" and not acceptable.
It would be much easier to use an alternative source for those shots in particular and start in a better place. I am pretty sure a better video source could be made available for those. Much less work then.
Now to address the point about "Barring an awful lot of work, there's only so much that Adywan can do with picture information which just isn't visible anymore, but I'm pleased he's managed to improve things overall now, as Lando's inconsistent shirt was particularly jarring from shot to shot for me."
The most annoying thing about this is that everything has to rest on Ady's shoulders and that we have reached a point where he is now working alone again. It is frustrating that an old VFX process (blue screen) causes the problems it does and the only manner with which to attempt a fix is a "Fake" fix. Then as you said you also have the 2004 crushed blacks. What would be wonderful if tasks such as these which are more "restoration and repair" based could have someone dedicated to this task alone so Ady could get on with the more complicated creations and actual editing.
The thing that strikes me is that there is an extra mile to go both in blue screen reversal damage on all the window shots or any shot with blue absent from blue screen removal that would pay off massively and crushed blacks re-instating lost detail. I will give my example of how to potentially approach it.
I don't disagree with Ady's color corrections but I did find here that the red needed to be shifted orange to get the natural tones out of it and lot's of yellow de-satuation and red de-saturation also. I then added the Blue lights ramped up the strip lights, and added crushed black detail for the round part in top right I tinkered with the light areas of Lando's shirt leaving the shadow color intact. I changed his shirt to try match the previous and the following shot as it is more this color perhaps due to lighting?
I did this as a still image, and whilst doing this yes I could certainly appreciate how long it would take to do this in terms of footage in say after effects which I do not have. But what I am saying is it would be good to have someone on this job alone mainly concerned with "repair and restoration" only. There is a very simple formula to it and does not fall in to the Adywan rocket science category :)
I am trying to give a bigger picture in terms of watching the new clip seeing some amazing new shots and then immediately noticing a quality drop due to the state of the special edition and the fact that it's never been quite right since the day the film was released and how far do you want to go with it? I put the ceiling at that point... blue screen reversal damage and restoring missing detail.