Next time you might want to post in
Why was my Wild Knuffel rejected? thread.
In my opinion he lacks in big changes... Like.. you can just throw out 2nd stage, make 3rd stage the second one and then change between 1-2 will be really visable. Personally, I'd add light skin, markings and hair from 5th stage to 4th stage and make it 3rd one, then add 4 and 5 ._.
He looks very plain in general and lacks in visable elements, I can see shirt, pants and hair. Tattoo/markings are almost not visable on his dark skin, the light violet skin of his current last stage is where I can finally really see them clearly.
What theme are you aiming for? Knowing what you want to create would make it easier to give advices on adding/changing elements.