Although I never developed it as far as a game, I did many years ago try to assign WW2 aircraft to a few broad performance bands based on their wing loading, power loading and rolling ability.
Power loadings greater than 350 HP per short ton at maximum power output and maximum take-off weight are classed as high-powered; if the ratio is below 250, they are considered sluggish.
For agility, aircraft with wing loadings of less than 25 pounds per square foot are considered extremely agile, those with up to 30 agile, and those with 40 or more heavily loaded.
My intention was to divide aircraft into a bunch of DBA-like classes, along the following lines:
STANDARD aircraft: Adequate all round performance: average power and agility.
Fighter (F):
Morane-Saulnier MS.406, Commonweath CA-12 Boomerang, Seversky P-35A, Dewoitine D.520, Reggiane Re.2000, Fairey Firefly I, Boulton-Paul Defiant, Brewster F2A Buffalo, Reggiane Re.2001 Falco II, Reggiane Re.2002 Ariete, LaGG-3, Curtiss P-40 Warhawk, Tomahawk or Kittyhawk, Bell P-39 Airacobra/Caribou, North American A-36 Apache/Mustang
Attack Bomber (AB1):
Il-2M or IL-10 Shturmovik, Curtiss SB2C Helldiver, Aichi E16A1 Zuiun "Paul", Yokosuka D4Y Susei "Judy", Aichi B7A Ryusei "Grace"
LOW POWER aircraft: sluggish, average agility.
No fighters in this class
Light Bombers (LB1):
Supermarine Walrus, Cant Z.501 Gabbiano, Fairey Barracuda, Fairey Battle, Junkers Ju 87D/G Stuka, Il-2 Shturmovik, Grumman TBF/TBM Avenger/Tarpon, Vultee Vengeance
LOW POWER AGILE aircraft: sluggish, agile.
Slow Fighters (SF):
Fairey Fulmar, Commonwealth Wirraway
Torpedo Bombers (TB1):
Fairey Swordfish, Auster AOP, Fieseler Fi 156C Storch, Interstate L-6 Grasshopper, Fairey Albacore, Kawanishi E7K2 "Alf", Vought-Sikorsky OS2U-3 Kingfisher, Douglas TBD Devastator, Grumman JF Duck, Ar 196A, Meridionali Ro 37, Nakajima B5N "Kate", Vought SB2U Vindicator/Chesapeake
LIGHT AGILE aircraft: high power, very high agility.
Light Fighters (LF):
Henschel Hs 123, Fiat CR.42 Falco, PZL P7, PZL P24, Gloster Gladiator, Avia B-534, Ikarus IK-2, Kawanishi Ki-27 "Nate", Mitsubishi A5M4 "Claude", Mitsubishi A6M2-N "Rufe", Polikarpov I-16, Mitsubishi A6M2 Reisen "Zeke", Nakajima Ki-43 Hayabusa "Oscar", Mitsubishi A6M5 Reisen "Hamp"/"Zeke"
No bombers occur in this class.
AGILE aircraft have average power and high agility, though not as high as the LIGHT AGILE class.
Agile Fighters (AF):
Meridionali Ro.43, Fiat G.50 Freccia, Macchi MC.200 Saetta, Fokker D XXI, Curtiss P36A, Curtiss Hawk 75A1 to A4 Mohawk, Curtiss Hawk 75N, Brewster B-239 Buffalo, Hawker Hurricane, Grumman F4F Wildcat/Martlet, Supermarine Spitfire Marks I to IV
Dive Bombers (DB1):
Westland Lysander, Blackburn Skua, Junkers Ju 87B Stuka, Douglas SBD Dauntless, Mitsubishi F1M2 "Pete", Aichi D3A "Val", Aichi E13A "Jake", Mitsubishi Ki-15 "Babs", Mitsubishi Ki-51 "Sonia", Breda Ba.65, Nakajima B6N Tenzan "Jill"
HIGH-POWER AGILE aircraft have high power loading and agility.
Fast Agile Fighters (FAF):
Supermarine Spitfire Marks V to VI, Supermarine Seafire III, Nakajima Ki-84 Hayate "Frank", Supermarine Spitfire Marks VII to 22
No bombers occur in this class.
HIGH POWER aircraft have high power loading and average agility.
Fast Fighters (FF):
IAR 80, Macchi MC.202 Folgore, Kawasaki Ki-61 Hien "Tony", Yak-1, Yak-7, Yak-9, Messerschmitt Bf 109E, Reggiane Re.2005 Sagittario, Fiat G.55 Centauro, Macchi MC.205 Veltro, MiG-1, MiG-3, Yak-3, Yak-9U, Yak-9P, La-5FN, Messerschmitt Bf 109F/G
No bombers occur in this class.
HIGH-POWER HIGH-LOADING aircraft have high power loading and high wing loading, hence poor agility.
Heavy Fighters (HF):
Kawanishi N1K1 Kyofu "Rex", Grumman F6F-3 Hellcat/Gannet, Nakajima Ki-44 Shoki "Tojo", Kawanishi N1K1-J Shiden or N1K2-J Shiden-Kai "George", Mitsubishi J2M2 Raiden "Jack", Lavochkin La-7, Yokosuka MXY7 Ohka "Baka", Hawker Typhoon I, Grumman F6F-5 Hellcat, Bell P-63 Kingcobra, Republic P-47C/D/N Thunderbolt, Hawker Tempest V, Focke-Wulf Ta 152H, Heinkel He 162 Spatz, Messerschmitt Me 163 Komet
Fast Attack (FA):
Nakajima C6N1 Saiun "Myrt"
HIGH POWER HIGH LOADING FAST ROLLING aircraft have high power loading, high wing loading, and very fast roll rates.
Fast Rolling Fighters FRF:
Focke-Wulf Fw 190A or D Wόrger, Chance-Vought F4U Corsair
No bombers occur in this class.
MULTI-ENGINE STANDARD aircraft have adequate power and wing loadings, but a poorer roll rate than single-engined types.
Bomber Destroyers (BD2):
Bristol Blenheim IF and IVF, Potez Po.630, Messerschmitt Bf 110C/D/E/F
Light Bombers (LB2):
Handley-Page Hampden, Mitsubishi Ki-21 "Sally", Mitsubishi G3M "Nell", Lockheed Hudson, Martin Maryland, Bristol Blenheim I and Blenheim IV/Bolingbroke, Blenheim V/Bisley, Breda Ba.88 Lince, Mitsubishi G4M2 "Betty", Polikarpov Pe-2
MULTI ENGINE LOW POWER aircraft are sluggish but adequately agile.
Light Bomber Destroyers (LBD2):
Messerschmitt Bf 110B
Bombers (B2, B3, B4, B6 according to no. of engines):
(B2)
Dornier Do 18, Caproni Ca.309 Ghibli, Grumman G-44 Widgeon/Gosling, Consolidated PBY Catalina, Douglas B-18, Grumman G-21A Goose, Caproni Ca.310 Libeccio, Focke-Wulf Fw 189 Uhu, Heinkel He 115, Martin PBM Mariner, Dornier Do 17Z, Henschel Hs 129A, Heinkel He 111, Armstrong-Whitworth Whitley, Vickers Wellington, Douglas C-47 Dakota, Nakajima Ki-34 "Thora", Fiat BR.20 Cicogna, Fiat RS.14, Caproni Ca.135
(B3)
Junkers Ju 52, Blohm & Voss Bv 138, SM.81 Pipistrello,
Dornier Do 24, Cant Z.506 Airone, SM.79-I Sparviero, SM.82 Canguru, SM.79-II or III Sparviero, Cant Z.1007 Alcione
(B4)
Short Sunderland, Consolidated PB2Y Coronado, Arado Ar 232B Tatzelwurm, Focke-Wulf Fw 200 Kondor, Kawanishi H6K5 "Mavis", Curtiss C-46 Commando, Short Stirling, Kawanishi H8K2 "Emily", Boeing B-17C/E Fortress
(B6)
Messerschmitt 232 Gigant, Blohm & Voss Bv 222 Wiking
MULTI ENGINE LOW POWER HIGH LOADING aircraft are sluggish and lacking in agility.
Night Fighters (NF2):
Junkers Ju 188, Dornier Do 217N, Northrop P-61B Black Widow, Junkers Ju 288, Messerschmitt Me 210, Heinkel He 219, Junkers Ju 88G
Heavy Bombers (HB2, HB4):
(HB2)
Bristol Beaufort, Avro Manchester, Junkers Ju 88A, North American B-25 Mitchell, Dornier Do 217E, K and M, Yokosuka P1Y Ginga "Frances", Junkers Ju 88S
(HB4)
Piaggo P.108 Bombardiere, Heinkel He 177 Grief, Junkers Ju 290, Boeing B-17F/G Fortress, Consolidated B-24 Liberator, PB4Y Privateer, Handley-Page Halifax, Avro Lancaster, Boeing B-29 Superfortress
MULTI ENGINE HIGH LOADING aircraft have poor agility but adequate power loading.
Heavy Fighters (HF2):
Bristol Beaufighter X, Nakajima J1N Gekko "Irving", Northrop P-61A Black Widow, Messerschmitt Bf 110G, Messerschmitt Me 410 Hornisse, De Havilland Mosquito XIVF, Lockheed P-38 Lightning, Northrop P-61C Black Widow, Gloster Meteor III, Messerschmitt Me 262 Schwalbe
Fast Bombers (FB2):
Martin B-26 Marauder, Nakajima Ki-49 Donryu "Helen", Douglas A-20 Havoc, Douglas Boston, Lockheed Ventura/Harpoon, Mitsubishi Ki-67 Hiryu "Peggy", Douglas A-26 Invader, De Havilland Mosquito 1B, Pe-2M, Pe-2MPF
MULTI ENGINE HIGH POWER aircraft have average agility but good power loading from their exceptionally powerful engines.
Fast Fighters (FF2):
Kawanishi Ki-45 KAIc "Nick", Westland Whirlwind
Attack Bombers (AB2):
Henschel Hs 129B, Kawasaki Ki-46 "Dinah", Arado Ar 234 Blitz
All the best,
John.