-Fix sanity issues. You can test your model without uploading it in the Utility tab, Model Checker.
-The gut-mesh should become visible as the model disappears into the ground.
-The model should not be visible even when it has gone under in Decay Bone. Fix visibility. I am going to have to check your other models for that, aren´t I?
-Reduce the amount of clipping during the walk animation, especially from the back. The front is often consistent and gives it a better illusion of being natural.
-Site rules demand a collision sphere.
-The health bar needs to be higher. Fix the extension.
-Center the portrait camera and portrait backdrop.