Officially I wish the default setting was "rewind to start"
I am going to humbly take that back. I did some experimenting with this and leaving it in auto-rewind mode just creates problems during too many other editing processes. So for now I am back to switching to auto rewind at the appropriate times when I want loops or stems to snap to the beginning of a project, then turning it off.
It would be nice if somehow it snapped to the beginning by default when importing stems though. Not a big deal.