The roll-rate of the XVI makes its maneuverability edge over the N1K unquestionable. Even the lowly Spit VIII out rolls the N1K at 300mph ias, and at low speeds it crushes it in the roll axis.
I would rather unperk the XIV and C-Hog than perk the XVI, but if it were perked, there's no way in heck that the masses would go to the Yak, and the Ki-84 breaks apart in shallow dives, so it's also a no-go.
The Spit VIII would see a huge bump in use, the La-7 a moderate bump.