I used to really love this story in the beginning. Somewhere in the middle I felt it started falling off. But now its in full gear again. Back to the Shingeki no Kyojin I love. These characters have developed so much. To see them all fighting together, despite their differences. They all have a common goal. Not necessarily forgiving one another, but understanding why they did what they did. You see the effect the long fight has had on all of the soldiers. They are tired of watching their friends die, but they are fighting for what they believe.
I used to have gripes about Erin being a one dimensional character. He's one note, all he wants to do is kill titans, nothing else matters to him, hes just an angry kid with no development. But now i see thats apart of his character. Sure at first revenge is all on his mind, even now it is, but he doesn't have much time left. He needs to go through these extremes to accomplish his goal as fast as possible. He wants to leave the world a better place than it was for him. Even if that means majority of the population being dead. From a kid hes been apart of this fight that he had no control over. Everything is predetermined, I imagine it must seem like hes meant to do it. In a weird twisted way Erin is justified in doing all this. This was always meant to happen. You cant fight destiny.