I like how Shadowheart and Astarion are "broken"

For me these two characters are the ones who endured so much hardship and can become so much better if they are given the right amount of help. Some of the other characters are really enjoyable but they are pretty fine on their own and you don't need to help them improve. But for me these two do and it's so satisfying to see them grow and help them forget about their troubled pasts.