My ol' list, fighters only.
VVS: The most unrespected national planeset in AH. The VVS rightfully deserves as many planes as LW or US or RAF planesets
* I-16: Nifty fun plane, an icon by itself symbolizing the early troubles of the VVS impacted by Barbarossa.
* Yak-7A: Started out as quikky substitute for the Yak-1 in shortage, then turned out to be the most common Yak variant of 1941
* Yak-1B: The evolutionary middle-phase of the 'light Yak' line which ultimately leads to the Yak-3. Great 1942 fighter
* Yak-3: The final stage of the 'light Yak', what the Yak-9U is to the 'heavy Yak' line
* Yak-9: The evolutionary middle-phase of the 'heavy Yak' line which ultimately leads to the Yak-9U. Great 1943 fighter
* LaGG-3: A noodlesplane which can't be left out in any real Eastern Front scenario/event
* La-5: The beginning of the 'Lala' legend, a much lacking predecessor of the La-5FN
IJN/IJAAF: So many pieces missing from the great Pacific War
* A6M-3: The big, missing, Zero between the 1941 A6M2 and the 1944 A6M5
* Ki-43: The most representative IJAAF fighter of the early war period
* Ki-44: A mid-war IJAAF fighter
* Ki-45: A Japanese twin-engine, heavy fighter, sorta like what the Bf110 is to the LW
LW: A most complete set, although perhaps one or two missing loops
* Fw190A-3: Not a crucial necessity, but a good, representative early war Fw190 suitable for post-BoB English Channel scenarios/events
* Bf109G-10: The high-alt, gap-closer between the Bf109G-14 and the Bf109K-4
RAF: Can't think of anything
USN/USAAF: Don't fediddlein' need any more
RA/other: Hey, they fought in the War, too. They should deserve it
* Re.2005: Comparable to the C.205, but substantially better high-alt performance. Excellent mid-war addition for the Regia Aeronautica.
* IAR.81C: The Romanian fighter, meeting 'their finest hour' at Ploesti
* D.520: A nifty French fighter almost being a match against the LW planes during the BoF
* M.S.406: The most numerous French noodlesplane during the BoF, good for BoF scenarios/events
* F2A: Have to satisfy the Finns, or else the world will come to Armageddon