As someone who is also into animation, I will preface this by saying that this is tough stuff to make look good. I liked some aspects of the models you used, but the animation was really rough particularly in the contortion of the models' bodies while fighting in some spots and some of the special effects could use some work as well(for example the lighting effect in the second half of the toon was a bit overdone. ) The story could use a bit more of a preface, too.
That said, I think you have some interesting ideas to present here. I'm looking at the Credits area and only seeing one name. Are you doing this by yourself or working in a team? If this is a one man operation then I can definitely say you've got your work cut out for you and that I respect your drive.
Most high quality animations (especially 3D, but whatever) have teams of people who work in a more specific area of animation be it modeling or animation or even textures. I have a modicum of experience in textures, for example, as my skills tend toward the 2D. But I've also done some modeling. Animating(boning, morphing, etc.) is my bane. lol.
I'm wondering what you built this in and whether you made the models from scratch or borrowed them from something else and edited them to suit your purposes here. (Neither is a knock against you. I'm just curious.) I'm also curious as to whether your going for the cell shaded look or trying to emulate/formulate something else.