I highly recommend sticking with full area even if it is difficult at first. Makes aiming a lot easier, and you don't have to do the awkward thing where you keep adjusting the tablet area because it feels "wrong", only to realize that everything was going to feel wrong when you're changing pointing devices anyways.
Also, I wouldn't worry about the grip at all. Just about any grip will work. I've seen some really dumb looking grips that work just fine, because as long as you are A) holding on to the pen, and B) able to move the pen from corner to corner, your body will figure out a way to make it happen.
Also, I wouldn't worry about the grip at all. Just about any grip will work. I've seen some really dumb looking grips that work just fine, because as long as you are A) holding on to the pen, and B) able to move the pen from corner to corner, your body will figure out a way to make it happen.