Currently the AI fly the same FM. The fact that some things don't affect it like wind, can make some behave differently.
We could stop that and make 2 FMs one for the AI to try to make it behave like it would, and a different Player FMs. We have also done many things to help balance but there are arguments the other way too, AI is not human, possibly never will be. Take away all advantages and then you will be the super ace winning the war, given already we have 1000s more hours than real pilots then.
Then balance is affected the other way too.
The RPM is not the problem per say FB, as I mentioned before. The craft climb and fly at speeds and alts as they should where possible for the player and turbo is adjusted based on engine/carb types
Testing is done by a player flying it so it's generally good for the player. AI are also checked to make sure that they can take off (and with other loadouts) and form up properly, and fly in formation etc with the player FM, and dogfight well, fly low, high etc, you get the idea.
They have "turbo" added in many cases to allow for a large variety in engine performance at altitude. Adding more power will give you the player a different FM, and boost it over the AI so yes you get a better craft.
P4 we are doing many things but exactly how it will all come together who knows.
OH and BTW just about all flight sims out there have similar AI issues. It's just not feasible to have the AI behave and fly identically to the player (until we have super computers at home), it's not a player it's a computer. However we have eliminated many issues along the way and think it's generally pretty darn good.