I think I have the best, and most likely explanation of the Shaw -> Chrinstiansen change.
The Shaw ghost was also of Anakin before he turned to the dark side.
The redeemed Anakin Skywalker was a bald head and a torso.
The image of what the pre-vader Anakin changed. Therefore GL, unfortuately, had to alter the force-ghost of the pre-vader anakin to match.
Audio Mix/video errors
Lucas was so busy getting done with RotS and having to meet a deadline for the DVD release that a large amount of the transfer went upsupervised by him, thus, the problems noted. The whole "Deliberate creative decisions" is LFL saving face to keep sales going until a better version is released. As for why it only happened to ANH, somebody wanted to try and mix the audio so that it still was mono and yet had surrounds, tested it on ANH, looked at it, realised it was bad, but didn't have time to fix it. The effect would have been so bad in the Battle of Yavin that the mixer pulled it down to make it less noticable. The color casting is Lowry's algo over-averaging the scenes to give it a grainless look to match the prequels.
Any requests?