Backwards,
As well as getting 18 yrs worth of Career Average, don't forget that the value of each year's contributions will be revalued by an average earnings index so you will also benefit from the effect of compounding and annual pay rises when they come back into play. Add your accrued benefits from AFPS 05 or 75 and you may have as good a pension as before, if not better.
With regards qualification for accrued rights under AFPS 75 or 05, all previous briefings/DINs etc remain extant. Therefore, if you were on a 38/16 or 40/18 engagement that finishes after 1 Apr 15, then so long as you complete that engagement you will be able to access those benefits (pension/EDP/lump sum) accrued up to the introduction of FAFPS at the same time you would have expected to receive them previously.
With regards the impact on high flyers, this will be something that the AFPRB, SSRB and NEM will have to look at to ensure remuneration packages remain competitive once the lower value of a Career Average pension is taken into account. There may be resultant pay increases at some levels so that people are paid better for doing the actual job, but unlike a final salary scheme under Career Average the State would not end up paying them a very generous pension for the next 30 years based on what could have been a relatively short period of their overall career.