I am curious, are we able to import Daz 3d characters into Character Animator? That would make the process a LOT more simple since y ou wouldn't have to deal with sprites.
I think best you could do is take screenshots. But I agree, I think a 2D/3D crossover would be interesting. Generate cycle layers for transitions etc.
But it would be hard - I would probably just use a 3D package for animating 3D characters (like Unity 3D Cinematics).