Since I'm a mecha head I would have added Getter Robo and Mazinger Z and their respective movies. I think american kids would have been responsive to super robot shows like this since Gundam Wing cleaned house when it debuted on the programing block.
I wonder if the 2002 Hunter x Hunter series could have been brought over too.
I must've only seen the later stuff then. If we're doing 70s anime, Astro boy should totally be on the toonami list as well.
Astro Boy would have been a perfect match.