I mean, it's not like she's gonna tell someone she just met, "Hey, wanna hear the stories of how I had to sacrifice some children when I joined my church?"
There are many many ways to put exposition in a fiction creation whether it's a book, a film, or a game, and they have a hierarchy of quality (for example, putting it in visual form is better than in dialogue, dialogue is better than a random book), it all depends on how good a writer you are
Considering you are ignoring the:
- the post-Raphael conversation where she brings up her knowledge of torture and manipulation
- the Priest of Pain scene where she gives him tips to torture people
- the goblin party narration bringing up how she enjoyed killing before
- the post tadpole dream #2 conversation about "wanting it all"
I'm not sure the problem is with the game not providing you with the information you want, and more that you are avoiding situations where the information is brought up and/or you fail to get the hints when it does.
She has more backstory explored in Act 1, it's just not in the part we have access to in the EA right now. I'm not sure if Larian is planning to include all of Act 1 into the EA either, but it should be there at release at least. Datamining is a wonderous evil gift.
