Inquisitor sapiens potensque said:
People are talking here like faith powers are something generally available for Sisters. I don't have the new Ecclesiarchy book yet, but unless something's changed the great bulk of Sisters do not have them. They require Fate Points, which NPCs do not generally have. Even in TT, if I recall correctly (I don't play the TT, but I do have all the codexes), they require Faithful characters, no? Or am I misremembering?
Also, the Sisters are not the Emperor's left hand, or any hand, they are the armed body of the Ecclesiarchy only.
In Blood of the Martyred they have changed some things. You are probably right about the original TT requiring a FaithFul character, but in blood of the martyr, and I think in IH too, the sisters get Pure Faith which is the start and prereq to other faith talents. Once Ascended, a Palatine can easily have 7 fate points, and there are some new talents that make some faith talents free, and again some others that allow a used fate point to be replenished, so an ascended Sister will deffinatly be bringing something unique to the table. There is access to these faith talents for others as well, though I think the Sisters have the greatest access.
Ok, so you dont like the hand allusion, how about Astartes are the Favored Sons(A Motto The Ultramarines Favor) and the Sororitas are the Favored Daughters(Their Old title was Daughters of the Emperor, later became Brides of the Emperor).