I would recommend the oft-forgotten
Kaiba. So many people avoid this one because of the style of animation, but it's story really is very touching at times, not to mention very creative.
Also,
Casshern SINS is fairly touching as well. I always like to point to the
4th episode, since it's a standalone ep, and gives a strong idea of the general nature of the show. The only thing that you wouldn't know from watching that 4th ep is what "The Ruin" is. The Ruin is the phenomenon that causes ALL the robots to slowly deteriorate until their 'deaths'(except the main char, Casshern). Yes, despite appearances, EVERY char is a robot.