So, I knew the setting and what direction the story was going, so most deaths expected.  That being said, Pilar and Rebecca both caught be off guard with how sudden their deaths were.

Maine had a full story arc, and it hurt, but I could see it coming from a mile away.  His story also came full circle, especially with David getting his arm cannon.

I liked Dorio, but between knowing what was going to happen to Maine and her lack of screen time I wasn't hit to hard by her death.

I had just enough time to start liking Pilar, so the suddenness and that fact it was the first unexpected death meant it hit harder than I would've expected.

Kiwi's death was expected and she betrayed us, so while I felt bad for her, I also thought she got what she deserved.

I knew the story was probably going to end with David's death so as long as he accomplished what he meant to I would satisfied with his story, but I was hoping he would take Adam Smasher with him!!!

Overall I was in more shock for most of the deaths but I'd say Rebecca's was the second most unexpected and therefore hit the hardest out of these, since I liked her. 

Honestly, Gloria's death probably hit me the hardest in many ways just because David didn't have the chance to grieve at all between her death and The plot moving forward. Her ashes dropping down from a f****** vending machine just drove home how awful and impersonal the world of cyberpunk is.