Despite the obvious visual issues, the story was ALREADY padded out to the make the movie- Tim Burton's original short story was extremely slight (like, Dr.Seuss-book length), with the only real characters being Jack and Santa. And the movie is only 70 minutes, and actually does drag in some places. The story is padded to its extent, I feel.
The movie has a very tight focus on Jack in terms of character (as it should), so any "padding" would probably have to focus on characters like Sally or Oogie-Boogie. Oogie-Boogie could actually use a bit more development, since he sort of just relies entirely on the the build up to and then his song, after that he's just... there, as an almost unnecessary antagonist. But I feel like doing that would be distracting.
"...everyone finally shut up, and the audience could enjoy the beginning of the Anatevka Pogram in peace."