I managed to pick up a 1997 DVD this weekend of ESB
I only skimmed over it but a few things I noticed straight off the Bat.
1.The AT-AT Binocular shot reveal seems to be much cleaner than the Special edition version and there is more definition in it.
2. As we said earlier on the page the Dish shooting the AT-AT Leg is better in the 1997 DVD and the shield generator getting hit is mildly clearer also.
3. Blue tinted stars during the asteroid field chase sequence really give the sequence something.. Although probably considered bad I really thought this was the best way I have seen it look in terms of atmosphere. I wonder if it was intentional but I doubt it. I started thinking of dust haze that could make the tint to the stars plausible.

I think if this look could be recaptured.. Perhaps this was the intention? but this is the main thing I took away after seeing the film.
Asteroid canyon also looked better too just slightly.
4. The music cues on Cloud city with the cloud car fly through removed are better than the special edition
5. Not listed on any SE change list when Lando, Leia etal are trying to escape cloud city the Special edition added "Look out" "Behind us"" audio for the crowd. Please use the GOUT audio on this one. But I still think it cut's off too quick when we cut to Chewie and R2 with the storm trooper in pursuit.
This is just some brief opinions after watching that really stood out to me that I wanted to share.