i cant see the problem with removing your oudside locks, removing your inside locks i can se a problem with.
as for the battery issue, just have a cable attatched to the positive terminal of the battery hanging at a secret place under the car, if your battery goes flat, hook up a battery to this wire (positive of battery) and hook the negative to the chassis of the car, simple!
just remember you can only do so much, as if they cant open the door they will break a window, try leaving the glovebox open with clearly nothing in it, and leave your centre console lid open etc.