P-39Q and P-40N are probably the Tony's most evenly matched opponents.
P-40F and P-38G are close but worse than the Tony with average pilots. However, the 38 is untouchable if flown well.
F-6F and P-38J are close but superior to the Tony.
Those sound like some fun fights with a p40N and 39. My money is still on the 61. The J could easily be a close fight depending on E state.
I think a hellcat would gain the advantage after a few turns being able to get slower, but I think Pilot capabilities certainly matter early on.
A g14, G6, or G2 can be a pretty close fight depending on pilot.
A spit8 might be a good one.
Ki61 really has a lot range with other fighters. Certainly could use a few more horses under the hood.