I don't think anyone can seriously suggest that we shouldn't go back and rescan or whatever they do to the film so that we can get these episodes in HD. Clearly this must be done by Paramount/CBS to prevent these properties from degrading into oblivion. I think for TNG/DS9/VOY it's not so much that they need to be remastered (which they do), but it's that they have to be completely re-edited as well (since all the editing was done on video). I would think that would be the real time-consuming (and expensive) part of the process. Remastering TOS seemed to me to be done on a shoe-string budget, but they did a remarkable job. Remastering TNG will be much more involved. And I don't think there's any way around the fact that the SFX will have to be redone. We could
choose to recreate the shots EXACTLY as they were, and that's all well and dandy. But at the bare minimum, GLARING mistakes should be corrected.
Defiant-2's registry should be NCC-75633. Riker's line about Yamato's registry being "1305-E" should be redone as NCC-71807 (while he's still alive!). "Brittain" should be fixed to "Brattain". "Melbourne" should be a Nebula-class ship as it was originally. Etc. Etc.