A review of the perk scale would be good, me thinks. The P51D and the Spitfire 16 could both use a jump, imo.
I think the scale needs to be more dynamic, currently most of the scale is tiered out in levels of 5, I say use a 2 through 60 scale. Things like the B29, P51D, Spitfire 16, Me262, Tempest, and a few obvious others should be at 5 or higher, and things like the C47 and Storch should be at 60. The SBD, D3A, and B5N should be in the 50-55 range.
In terms of GV's, I really think HTC needs to re-evaluate their current ENY values. The Panzer IV F has a score of 40 and the Panzer IV H has a 25??? If HTC was using only the short barreled version to score that then maybe, but as it is the F is just slightly behind the H in terms of AP ability. The lack of a top mounted MG may give another 2-3 points, but not 15.