I'm gonna go with Niko. He's tormented over what happened in the war and he desperately wants to forget about it. He'll also do whatever it takes to keep the people he cares about safe.
His deep conversations with Roman, Kate and Ilyena Faustin are a great representation of his personality and how he wants to be a good person.
Luis is another one. He takes so much sh*t from everyone around him and still remains loyal.