It wouldn't take that much work as it's just a 3 hour mini series rather than 178 episodes of a TV series. There are bits that Kenneth Johnson talks about on the DVD commentary in regards to the effects that he wished were better such as the smoke trail from the shuttle so when I mentioned sprucing up the effects I mean let Johnson go back and redo any effects that he didn't feel worked out. Not a Star Wars-esque CGI mess. Models look more believable than CGI anyway.

Keep the original effects, remaster the film (but preferably not use the teal/orange palette that many remastered shows have used, especially the Reeve Superman movies), use the original audio (why did they change sound elements??), use the original aspect ratio (1983's was futureproofed and framed for 16:9 but TFB was clearly framed for 4:3 in mind)
Even if some changes had to be made, I'd buy the blu-ray. The model work and f/x of the time hold up very well for the most past and it's also a testament to those who did the work to make it possible. A separate option for remastered f/x might be nice, if the original film elements still existed (they might not) but that would take a ton of work (like Star Trek TNG).