That is a very good idea / suggestion! I haven't learned / experiemented with that yet, but had sort of naturally ruled it out as I've only seen ActivatePersistentLevelTemplate been used in the campaign like... Perhaps five-or-so times? And almost none of their level templates that I recognize from the campaign are set as persistent so I drew the conclusion that it can't be the case. But, now as you mention it, I do recall having read something about a travel agency and transporting characters/items cross level.
I'll experiment a bit and return with what ever my results may be.