Getting a barrister on the case is the best thing. Never forget that the presumption is for development.
Justiciar - yes it does work. I've done that trick, although more by accident than by design, and it worked brilliantly. It also eases subsequent applications because they know if they throw yours out for no good reason you will immediately appeal and make them look silly.
The planning system is designed to put hurdles in the way of ordinary people who then give up because they don't know how it works.