No need to worry about the late response.

Instead of a morph, make a face that only includes the morphs you want to change.  Or make a face that only includes the morphs you want to restore.  For instance, when you save a face, there is a little button that says "Select Subset".

Click on the "Select Subset" button and a list of all the morphs in the figure will appear.  Click only the morphs you want in the face, and then give the face a new name.  In this case I named it "Bruce default 12052014".  That way I know it's Bruce's plain face as of Dec. 5th, 2014.  Then you save the face.

Now, I can screw Bruce's face up any way I want.  I can give him donkey ears, make him really mad, make his nose really big, or make a new face with a huge amount of changes, and when I want to change him back to normal, I don't have to remember what morphs I changed.  I just choose the face "Bruce default 12052014" from his library of faces and apply it, and back he goes in a flash.

The same thing can be done if you only want to change certain things.  Let's say you wanted to make a face that left the face unchanged but changed the ears and mouth to cat ears and a cat mouth.  Then you'd make a new face as above and only include the ear and mouth morphs.  That way when you apply it, ONLY the ears and mouth will change.  Or let's say you wanted to make a new face that restored his ears to the normal ones he has now but left all the other face morphs alone.  Then what you'd do is, while he's in his normal state, you'd make a new face that only includes the ear morphs.  Or let's say you made a custom morph on his face and you want to make a way to apply only that morph.  Then you'd make a new face that only includes the custom morph (or morphs).  If that custom morph changes any part of his ears, and you didn't want it to, simply choose the new face that ONLY changes his ears to a normal state.

That's for the face.

But you can do the same thing for the body with poses.  Make new poses, but only include the morphs for the bodyparts you want to change by using the "Select Subset" button to select the morphs to be included in the new pose.  Include morphs that are already in the figure, or custom morphs you made yourself.

As to your other questions, the "full" setting for morphs is indeed 1.  What might be happening is that other morphs were included in that morph that are contributing undesired effeccts to the desired effect.  When saving morphs, only the ones that need to change should be saved in it.  So if you save a new morph, say, one that makes a clown nose, and the ear morphs were not set to 0 when you saved it, then the "Clown Nose" dial is going to make the nose AND the ears change.

As to your last question, that depends on whoever made the morph, and it might have something to do with what I just said above.  Maybe, by accident, the maker of the morph forgot to set a "HeadLarger" morph (or something similar) to 0 when he made a new character morph.  Consequently, applying the new character morph is going to make the head bigger too.