Lets put things into perspective...
While is possible that someone or even group of someone's will fly to LPF in late war planes like P-51 or Dora, that shouldn't be big problem because they would have to fly 20 minutes to get in LPF. Then they would have to meet slower but more nimble fighters. And if they score any kills they would be quite worthless in perk point sense.
And even then it would be much better situation than we have now, early war planes do not get use almost at all and they can be gangbanged by late war monsters all the time.
Biggest problem would be capturing territory, especially if one country captures whole LPF. When LPF is far away from HPF, almost only possibility for other countries to gain foothold in it would be massive bomber mission or CV.
I think it would be wise to divide arena to three fronts, low, medium and high. They would be populated with early, mid and late war planes. This might be good idea but it would require more arena area used for dividing seas or other obstacles.
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jochen / Gefechtsverband Kowalewski
Units: I. and II./KG 51, II. and III./KG 76, NSGr 1, NSGr 2, NSGr 20.
Planes: Do 17Z, Ju 87D, Ju 88A, He 111H, Ar 234A, Me 410A, Me 262A, Fw 190A, Fw 190F, Fw 190G.
Sieg oder bolschevismus!