With Sublime Merge build 1070, we show stashes exactly the way git stores them, and how git will show them in its graph.
The odd thing about stashes of untracked files in git is that they are stored as a separate parent commit. If you make a stash with untracked files in 1070 and click the commit graph circle next to the stash, you'll see we expand the parent nodes in the commit graph. In fact the stash commit will have three parents. One is what HEAD was when the stash was made. One is a commit with the contents of the index when the stash was made, and the final will be the untracked files.