I don't think that the F3 Mode makes much of a difference, its a very good training aid for combat flying. It allows you to watch the control surfaces and see the fight from a wider perspective. I think that the in cockpit skill comes from the duel, the 1v1 fight in the MA. The MA is where you become an ace pilot.
The DA to me has been the TA. When I want to try a new move, or a new plane, if im bored and looking to screw around. I hop in the DA and make some noobs miserable.
Keep F3, it keeps the HAWX and BLAZING ANGELS wannabe crowd happy, it gives us more baby seals to club and its very useful if we wanna do some training and view how some aircraft operate.
My 5c (Aussies dont have 1 or 2c coins anymore)