Elements of the movie were not to my taste. Apparently you require someone to fully accept the entirety of a movie or they cannot consider themselves a fan.
Star Trek is not about killing. It's not about vengeance. It's not about revenge. It's about hope. It's about humanity growing up to be better than we are. About not giving in to our base emotions and our fears.
You have no problem with Kirk killing Nero while he was helpless. You were cheering him. Hopefully Kirk will kill lots of people in the sequel so you can cheer some more. Me, I always hope that they can find another way. They don't always succeed but it's nice to see them try.