The Simplicity of the speech is great, Lucius was safe, slaves are freed, Rome is to be how it was and Maximus is with his family. Maximus stresses repeatedly at the beginning of the film that he's just a soldier. His last act is simply that, carry out the mission. Not as glamorous as "are you not entertained?" Or his earlier speech in the coliseum, but it's in character and wraps up the story.