One area that hasn't been showcased in a 'preview' sense is the audio of this new edition. I'm curious as to how much raw ADR takes they have access to for the bridge portions of the film. Watching the Director's Edition DVD recently, it really sounds like the sound team only had the finished audio mix to work with because some moments feel rough. For example, the first attack on the Enterprise from the theatrical edition.
I remember when I saw the anniversary screening of the theatrical cut a couple years ago, I noticed a lot more background audio than I was used to. I assumed it was the theater using more of the mix than the stereo speakers I'd normally hear the movie with, but I was flipping through the new 4K release, and that also had the same additional background noises.
I do hope that the new mix is a bit closer to the TE than the 2001 DE was. I liked the additions, the bridge noises and the extra bleep-boops from button pushing (especially the transporter button), but the replacements never quite sat right for me. The more electronic-sound warp-drive sound, the additional screaming for the V'Ger energy bolts, and especially the new red alert alarm, which always went on too long, and never felt like it belonged in the scene, but was just overlayed on top (oddly, the different alarms that were added in the Engineering scenes sounded good to me).