My thoughts on the unicorn scene:
On it’s own, I actually find it quite beautiful. I feel it is visual imagery for Deckard’s desire to simply break free and get away from the awful reality that is his life, his occupation.
The issue with the scene is that it ties into the Unicorn origami at the end and basically says Deckard is a replicant. I think the interpration that Deckard is a replicant makes the entire movie fall apart on itself.
So again, final cut is a more polished version (cleaned up special effects and so on) of the DC, with one (admittelly beautiful) out of place scene that messes up the films main characters.
Final cut - unicorn scene = sci fi perfection