This is just a personal interpretation but I think of them as just regular people who are painted as idealism for the era of history they represent. In Dolores Rei's case, there is a lot of heart warming, loving, and empathetic wording involved with how she makes people feel. Even Mr. DuBois sees Dolores Dei as this ultimately heart warming figure that immediately has him bring out feelings for his ex but we learn why that is such a delusion (in the case of his ex). Our encounter with the Dolores Dei in her church invokes these sort of idyllic feelings. The church is also completely dilapidated and falling apart.

From what I gathered, Dolores Dei is intentionally depicted as shining and radiant because if she were to no longer have that light, the truth around you is exposed by said lack of light. Every single feeling that she makes people feel are ultimately as weak as a ray of light that you can move your hand through. It's just as easy for said light to re-emerge.

If you look at her depiction, on the glass, she is showing her usual rays of shining hope while a small figurine is held between her fingers, a soldier figurine, to be exact. I see this not as a bait-and-switch interpretation but more of how idealism can blind anyone and anything to the ugliness of the world.

Her own bodyguard killed her for seeming "un-human". It's also implied that she may have carried out several military operations during her period of history.

Deification of our ideal history, not our real history.