I haven't detail-checked the frame-by-frame running animation of your hero, but it looks that he's moving left arm and left leg forward together. That might explain why the run "looked odd" to me previously, as usually, you swing arms and legs in opposite directions to keep balance when running.
I similarly note that your hedgehog lifts both right legs together and both left legs together. Camels do that, and afaik, very few other animals do. It gives the HH somehow an "army" look that you might want to reinforce (camouflage, rambo style, whatever) or you could prefer to make him lift opposite legs (e.g. front-left and back-right) together, as most 4-legged animals would do.
No antenna on the snail ?
They all have an adorable look, aniway.
i have no idea on how this new tail would move in an eventual animation
twisting left and right ? It must help him keep balance, anyway.