". Flying less-expensively equipped light aeroplanes which don't need the same level of avionics as are needed to teach the JAR-FCL PPL"
I don't see many schools getting a special aircraft to teach the NPPL and in fact there is nothing to stop them teaching for the JAR licence on a more basic machine (though you may need just a couple of hours on something better equipt) so the hourly savings will be negligeable. Yes you CAN finish the NPPL in less time, but how many will? The concensus seems to be very few, so for most, the only real savings are on medical and licence costs.
The main benefit I see for this licence is for those that can't get a class2 medical.