It's funny that you mention Heavy Metal since they used a form of rotoscoping in some scenes to add realism to their characters - an art form replaced with motion tracking which never really did it justice. Mine would be somewhere in the middle. The Characters would be cg, but have the look and feel of comic book art while being rendered in a computer. Keep in mind, this is not "motion-comics", that's just lazy.

It's difficult to describe since I really haven't seen anyone doing what I have in mind, but the characters in the film "Appleseed Ex Machina" is a step in the right direction. It will have the look and feel of drawn comic book art, but rendered in a computer without the obvious "video game" look. The problem with a lot of cg animation today, is that it just looks too fake and that pulls the viewer out of the story. I want to avoid that.