I think the PFA facilitate coaching in skills beyond the PPL - e.g. tailwheel, strip sense, exploring the flight envelope etc.... - but I have a feeling this applies to people who own or part-own their own aircraft.
It's worth checking it out on their site (must admit I havent had the time to do that).
A guy I shared a Jodel with a few years back did it - he reckoned it really sharpened his skills and awareness up.
www.pfa.org.uk