As in modifying areas such as the underside of your head (visible when you look up), the side of your arm facing your torso (visible when you walk), etc.
I've been to a number of different skin editors but they always keep your player at a typical stance with these areas closed off. Any suggestions?
MC Skin 3D allows you to hide body parts, so you can get to those hard to reach areas.
I personally don't use editors. I tend to edit my skins directly onto the file in editors such as paintDOTnet or Photoshop. I recommend doing this over using an editor in all honesty.