What about Staffordshire Bull Terrier?
If you train them properly and make sure everyone in the family knows how to treat it properly with love and respect then they can become an amazingly loyal companion for the whole family.
Again there have been a few issues in the media with them, but the majority of the time its a dog that has been brought up by irresponsible owners, and trained to fight/be aggressive. My dads staffie, Pip, is an amazing dog that we got from a rescue centre, and she is the most lovable pet that I have had. She enjoys nothing more then human contact and frequently tries to come for a cuddle and just sit by you, but she would also defend any of the family or the house with her life, in order to keep us safe. Her bark is very boomy which would is a great deterrent, and im sure the sight of 30kg of pure muscle flying at the scum that tried to break into my dads garage made them shit their pants a couple of years ago.
Would highly recommend one