Editing of a Character Rig

I have a human character rig that needs to be edited to work more properly. I got the character and the rig from someone I hired, but cannot do things like move the arms of the character without getting distortions in the skin such as bones sticking up. I just need to be able to move the arms and the skin move with the bones naturally. The character is fully clothed so you might want to hide the clothing, which is separate geometry, to fully see what I am talking about. This is really not my cup of tea so help is needed and tweaks may need to be made. It would also be a major plus if a face rig could be added as well. I will be transferring the model between 3ds max and maya