Leonid - I think P-63 would be a much better competitor than the P-39 when you look at the current planes in AH.
With the laminar flow wings, two-stage supercharger, and water injection, this plane could do 425 mph at 25,000 feet and climb in excess of 4500 fpm. Ailerons were reported to be excellent even at high speeds, and the turn performance was significantly better than anything in the US arsenal. This plane would be a monster in a dogfight.
Armament was 2 x .50 cal in the nose (200 rounds each), 2 .50 cal in the wings (900 rounds each) plus an improved 37mm cannon (M10) with 58 rounds. More lethal armament than the P-39, and a much longer firing time.
2400 of these were supplied to the USSR, which is a very large number compared to N1K or Fw 190A-8 production.