I am assuming that you are lumping extended cuts, special editions and all non-theatrical release versions under the broad category of “Director’s Cut”.

Also to echo what Onomatopoeia posted, all of them.

With all of that said, I have found every Director’s Cut of James Cameron films to be worse than their theatrical counterparts.

Cameron tried to clean up the ending of The Abyss and just made it more silly than the theatrical version.

The additional stuff he added about Ripley having a kid in Aliens wasn’t bad, it was just unnecessary as was the stuff with Newt’s family finding the ship. All of that just messed with the paceing of the movie. Also there is a scene with auto machine guns that has made it into “edited for TV” versions that really don’t belong.

All the stuff he added to Terminator 2 was meh.

I am not going to comment on the Avatar non-theatrical cuts as people love to bitch about those movies.

Cameron is a very focused strong director and it is easy to see why the stuff left out of the theatrical versions of his movies wound up on the “editing room floor”.