Count me in among those who loved it. Sure, it has a few flaws, but overall I really, really liked it. So yes, he killed Zod. He didn't actually want to, but he did it when there weren't a whole lot of other choices. As for saving more peoples lives, well, he's still a newb in this movie, and Zod was 100% calling the shots in the last movie. I don't see how he could have saved so many people, because for every second he spends saving a life, Zod could kill 10s or 100s of people. It kept me engaged the whole time, unlike Avengers (I just can't see what people see in that movie, unless it's because it's the cherry on the top of the cake. By itself it's really bleh).