I was thinking about the theory I've seen that Shadowheart was a Selunite brainwashed to go on a suicide mission for Shar, and how she mentions her memories will be returned to her in BG, but I might have understood it incorrectly. I was assuming she would have been a Selunite recently brainwashed to go on this mission but now I'm wondering if the mostly nice person we know from the EA is a result of all her memories as a Shar cultist being taken, leaving behind the person she was before being broken into Shar worship, a personality potentially many years old, many years of very unpleasant things.

This would set up the potential for a drastic character shift later in the story, we'll potentially be dealing with a very different person, possibly one more upfront with their alignment. I'm not sure how well this kind of twist could play out, especially with SH as a potential PC. I guess this was a bit more obvious to most people, and I don't know if the data-miners have weighed in.