Hmmm CH should be taken as a different universe, there are some minor changes, but I think that the different universe aspect was to stop Kaori's fans from lynching the author....
Killing in CH did happen, but you never really got to see it (none spring to mind) and the ones that happened were not glorified at all. The City Hunter deals with elements that the law can't/won't tackle and Ryo with his reputation and skills has many ways of dealing with things.
I wonder about how girls talk and is the style based on their influences and what they are trying to gain in life. For example squeeky schools girls acting cute because that is how their peers act. Shang Yin as Angel Heart never had those influences, its more like you fail to meet their expectations you die. If she was train to be a spy then a cute voice and mannerism would be suited?
I hate the last OAV of Kenshin that made me want to puke
If you characters like Revvy I really recommend you check out Poison Elves. Its an American comic, but the similarities of the two main characters is scary. I guess telling a story about a character having a hellish childhood transcends the country an author is from.
If part of why you are burnt out from the "I will not kill anime" is because they get a bit light hearted and bubbly then AH may not be for you. CH/AH generally has good resolutions to it's arcs. Ryo normally saves the day in some funky fashion and the victim sails off on a ship free from whatever was plaguing them (and with a suitcase of mob money to boot). I have to say especially in AH the actually arcs themselves I think are very deep and well told. For me it isn't as much about Shang Yin, rather it is about Ryo and how he is copying with loosing Kaori. This for sure is because I carry so many memories about CH, I have to admit I was moved to tears each time they show a Ryo/Kaori interaction.