Aside from rushes Princesses actually do a pretty decent job of brute forcing many story maps. I did the whole first pick rigmarole several times before settling on an account that had Sybilla and while she doesn't have an all-mighty tanking skill like Karma or Olivie the fact of the matter is that she still hits like a truck and she still has very high defense. She often stands aside during tight event maps but when it comes to just leveling your way up to Return to Ruins you can oftentimes just throw her out there to murder things without bothering with healing support.