Look at the US planeset and then look at other nation's planesets.
And 1/3rd of those U.S. planes are bombers and a cargo plane. *yawn* All of which, if they were removed from the game tomorrow, I would barely notice.
Fighters my man, lets stick to planes actually worth caring about.
The plane sets you will call limited, Russian and Japanese, yes they may be numerically smaller but these numbers include many of the best-modeled planes for typical MA conditions. Some of the latest, rarest, and/or highest-performance variants built, but the USAAF is stuck with 1944-eque performance for its P-51Ds and P-47D-40s