I think the new NPPL will be of great (financial) benefit to many existing PPLs, particularly those with JAA PPLs which have to be renewed (more money) every five years.
The difference between the typical £100 every year for a 50+ pilot to an AME and poss £10 to get your GP to countersign your self-cert medical is significant and AME fees have gone up much more than inflation in the past few years. I'm not expecting them to go down in the future either.
Those who fly PFA aircraft have permit limitations on the aircraft that prevent IMC flight or even night flight so the new licence will suit many PFA group members who don't fly abroard.
Its no good to me because I do fly abroad and have an IR, but I thoroughly support the new NPPL and appreciate the work that so many have put into bringing it about.