As it was put to us, greater oversight of air displays including Enhanced Risk Assessments, requires four additional people (2x Flt Ops, 1x Airworthiness, 1x Admin Support) which equals £250K pa. The CAA Board have directed that this cost is met by the user, this year. Might not agree with it but couldn't argue with the maths.
There are other changes to DA/DAEs which I am not really qualified to talk about but others have eloquently. Many seem sensible, others not so.