For example you could Ressurect Halsin if you were so unlucky so he died while you were rescuing him ... or Kanon (that Tiefling you mentioned) ... or that Druid in secret passage ...
And many more who would be probably just gratefull that you ressurected them.
But then there is question how about potentialy hostile NPC?
It would be certainly interesting to be able to "torture the thruth out of Spike" (or those "paladins" in tollhouse) by killing him and ressurecting him over and over. O_o
I doubt they could make it to where you could use a scroll on NPCs, especially ones that are involved in a protect/bodyguard quest. That would basically eliminate the whole part of the quest of keeping him alive.
