That's what makes it so great. ^_^I was also really disappointed with the anime so I started reading the manga last week, it's definitely worth it, if you don't like the manga then I just don't know what to do anymore.
IMO, they might've killed off a bit too many characters than was actually needed but they showed their willingness to kill off characters, that's what makes it good too.
It's like you never know who is going to die or when they're going to die because there is no plot protection for anyone except Tatsumi and maybe Akame, it's survival of the fittest.