Animation and 3D don't always go together.
What EnactJudo meant is that using 3d in the environments and background make your animation not look as good as it could be if it was all animated/cell shaded. I also have to agree with him. It's really hard to integrate 2d animation and 3d together without there being an extreme break in immersion. I like the animation, I just wish you could have animated the whole thing.