Looking at a lot of concept art in terms of body shapes and proportions for robots. The good thing with machines is that the limb size and shape can be unbelievably exaggerated without really defying reality, things can be done that would not be possible in human or organic forms.
These two images show how different body shapes can complement roles with the first having huge arms and upper body to support a shield. The second has achieved a more agile look. Even with these differences a similar aesthetic is achieved.