So, I read your message thinking "I have nothing to add, I don't fly combat". But...
The ESC current limitation isn't going to affect performance, it's only going to affect when ESCs burn up. And different ESC brands with the same ratings will act differently at any rate, because some manufacturers do something with the truth that marketing people call "making it look more attractive" and which ordinary people call "lying". Going to a higher rated ESC may gain you some tiny advantage in lower resistance, but it's going to take that away with more weight.
The airplane performance is really going to be affected by the prop used, the number of battery cells, the voltage constant of the motor (so-called Kv, although this term is only used by the model industry), and the total resistance in the system.
I'm trying to think of the best way to set your rules to put everyone on a level playing field, and the best way I can think of is to either call out a specific part number of motor (and hope the manufacturer doesn't change it), or to allow anything that turns below some specified RPM with the regulation prop, with a fresh battery.
What do the 'lectric RC racers use?