Pay more money for grant/renewals? No thank you, not voluntarily. There is no direct correlation between the cost of the certificate and the quality of service, especially in such a decentralised system.
However, as most police forces make an operating loss on their FLDs, I can see there could be some price hikes in future. In the immortal words of Yazz:
There is no way the majority of constabularies are currently discharging their mandated responsibilities towards the FAC/SGC holder community at the moment, and this is down to a lack of will at the upper echelons of those constabularies, rather than problems that can be immediately solved by a cash injection.
10 year certificates? Considering that after every gun incident carried out by a legally-held weapon in the hands of the FAC/SGC holder, the overwhelming view from officialdom is that the renewal process at 5 years is too long. Read the newspapers and you will see that there have been opinions from serving police officers involved in licensing that FACs/SGCs should be renewed ANNUALLY! Clearly, a knee-jerk reaction and one that administratively would be unachievable but you can see the institutional resistance to a 10 year certificate.