in addition to OP's suggestion... how about this?
1. Instead of perking planes, how about giving planes such as Tempest 0-ENY? Still flyable but 0-ENY. I think this is necessary to nudge people to fly other diverse planes and not stick to 1 uuber variant

2. In late war arena there should be late war planes only (excluding selected bombers)
example:
- mid war arena = mid war planes only (excluding some selected bombers)
- early war arena = early war planes only (excluding some selected bombers)
- late war arena = late war planes only (excluding some selected bombers)
here's how its gonna look like
Early war: 1940-1941USAB-25C ... 1-41
C-47A ... 12-41
P-39D .... 10-41(ETO)
P-40B ... 1-41
P-40E ... 8-41
F4F-4 ... 9-41(ETO)
SBD
***US needs navy torpedo bomber such as TBD Devastator for this time frame***BritainBoston MK III ... 5-41
Hurricane Mk I ... 5-40
Hurricane IIC ... 4-41
Spitfire Mk IA ... 8-40
Spitfire V ... 4-41
FinlandB-239 Brewster ... 3-40
SovietI-16... 1-40
***USSR sorely needs the followingfor this time frame***
Fighters: Yak-1, LaGG-3, MiG-3
Bombers: IL-4ItalyC.202 ... 11-41
***Italy sorely needs at least a bomber, and Fiat and Reggiane fighters***JapanA6M2 ... 7-40
B5N2 ... 7-40
D3A-1 ... 7-40
G4M1 (new model, coming soon)
***Japan sorely needs the following for this time frame***
Navy Bomber: G3M
Army Fighters: Ki-43-I, Ki-45
Army Bombers: Ki-21GermanyBf 109E-4 ... 5-40
Bf 109F-4 ... 6-41
Bf 110C-4b ... 8-40
Ju 88A-4 ... 5-41
Ju 87B
Ju-87D
***Germany sorely needs Dornier and Heinkel bombers***Mid war: 1942-1943USAA-20G ... 5-42
B-17G ... 6-43
B-25C ... 1-41
B-24J ... 5-43
B-26B ... 5-42
C-47A ... 12-41
P-38G ... 11-42
P-39D .... 10-41(ETO), 4-42(PTO), 5-42(EF)
P-39Q ... 10-43 (PTO) 11-43 (EF) 1-44 (MTO)
P-40E ... 8-41
P-47D-11 ... 3-43(D5)
F4F-4 ... 9-41(ETO),5-42(PTO)
F6F-3
F4U-1 ... 2-43(ETO)
F4U-1A ... 7-43(PTO)
SBD-5 ... 5-43
TBM-3 ... 2-43
***US needs P-40L and N army fighters for this time frame***BritainBoston MK III ... 5-41
Hurricane IIC ... 4-41
Hurricane IID ... 6-42
Lancaster III ... 3-42
Mosquito Mk VI ... 7-43(ETO),11-43(PTO&CBI)
Seafire IIC ... 10-42,11-43(ETO)
Spitfire V ... 4-41
Spitfire VIII ... 7-43
Spitfire Mk IX ... 7-42
***Britain needs Hurricane Mk IV and Spitfire Mk XII for this time frame***SovietIl-2 Type 3 ... 10-42
La-5FN ... 3-43
Yak-9T ... 1-43
***USSR sorely needs the following for this time frame***
Fighters: Yak-1, Yak-7, Yak-9D, LaGG-3, La-5, MiG-3
Bombers: Pe-2, Tu-2ItalyC.202 ... 11-41
C.205 ... 1-43
***Italy sorely needs at least a bomber, and Fiat and Reggiane fighters***JapanA6M5b ... 8-43
B5N2 ... 7-40
D3A-1 ... 7-40
G4M1 (new model, coming soon)
Ki-61 ... 6-43
***Japan sorely needs the following for this time frame***
Navy Fighters: A6M3 model 22, A6M3 model 32
Navy Bombers: D3A2
Army Fighters: Ki-43-II, Ki-44, Ki-45
Army Bombers: Ki-49-IIGermanyBf 109F-4 ... 6-41
Bf 109G-2 ... 6-42
Bf 109G-6 ... 2-43
Bf 110G-2 ... 5-42
Fw 190A-5 ... 6-43*
Ju 88A-4 ... 5-41
Ju-87D
Ju-87G
***Germany sorely needs Dornier, Heinkel, more Junkers bombers/variants, Henschell HS-219***Late war: 1944-1945USAA-20G ... 5-42
B-17G ... 6-43
B-25C ... 1-41
B-25H ... 9-44
B-24J ... 5-43
B-26B ... 5-42
B-29
C-47A ... 12-41
P-38J ... 12-43(ETO) 2-44(PTO)
P-38L ... 7-44
P-39Q ... 10-43 (PTO) 11-43 (EF) 1-44 (MTO)
P-47D-11 ... 1-44(D11)
P-47D-25 ... 5-44
P-47D-40 ... 1-45(ETO)
P-47N ... 6-45
P-51B ... 12-43(ETO),8-44(CBI)
P51D ... 5-44(ETO),1-45(CBI&PTO)
FM-2 ... 6-44(ETO),10-44(PTO)
F6F-5 ... 7-44
F4U-1 ... 4-44(ETO)
F4U-1A ... 7-43(PTO),12-43(ETO)
F4U-1D ... 1-45
F4U-1C ... 4-45
F4U-4 ... 4-45
F6F-5 ... 7-44
SBD-5 ... 5-43
TBM-3 ... 2-43
***US needs P-40N army fighter and SB2C dive bomber for this time frame***BritainBoston MK III ... 5-41
Mosquito Mk VI ... 7-43(ETO),11-43(PTO&CBI)
Mosquito B.XVI ... 1-44(ETO)
Seafire IIC ... 10-42,11-43(ETO)
Spitfire VIII ... 7-43
Spitfire Mk XIV ... 5-44,7-45(CBI)
Spitfire Mk XVI ... 7-44
Tempest V ... 5-44
Typhoon IB
***Britain needs Hurricane Mk IV for this time frame***SovietIl-2 Type 3 ... 10-42
La-5FN ... 3-43
La-7 ... 6-44
Yak-9U ... 7/8-44
***USSR sorely needs the following for this time frame***
Fighters: Yak-3
Bombers: Pe-2, Tu-2ItalyC.205 ... 1-43
***Italy sorely needs at least a bomber, and Fiat and Reggiane fighters***JapanA6M5b ... 8-43
N1K2-J ... 1-45
G4M1 (new model, coming soon)
Ki-61 ... 6-43
Ki-84-la ... 8-44 (CBI),10-44(PTO)
Ki-67 ... 4-44
***Japan sorely needs the following for this time frame***
Navy Fighters: J2M
Navy Bombers: B6N, D4Y
Army Fighters: Ki-43-III, Ki-44, Ki-45, Ki-100GermanyAr 234B ... 12-44
Bf 109G-6 ... 2-43
Bf 109G-14 ... 7-44
Bf 109K-4 ... 10-44
Fw 190A-5 ... 6-43*
Fw 190A-8 ... 2-44
Fw 190D-9 ... 12-44
Fw 190F-8 ... 4-44 (
replaced Ju-87D in frontline service)
Ju-87G
Ju 88A-4 ... 5-41
Me 262 ... 10-44
Me 163 ... 9-44
Ta 152H ... 1-45
***Germany sorely needs Dornier, Heinkel, more Junkers bombers/variants, Henschell HS-219 and Me-410***0-ENY planesEarly warHurricane IIC
Mid warF4U-1A
P-47D-5
Mosquito bomber
Spitfire VIII
Spitfire XII
La-5FN
Bf-110G
late warP-38L
P-47N
P-51D
F4U-1C
F4U-4
B-29
Mosquito bomber
Spitfire XVI
Spitfire XIV
Typhoon
Tempest
La-7
N1K2-J
Bf 109K
Fw-190D
Ta-152H
Me 163
Me 262
Ar 234