Having trained as a heavy anti-armor infantryman for 6 years, I can tell you that trying to spot armor from a distance in real life is far harder than even FC2. And I was one of the best in the unit.
Why do you think the military uses vehicle identification panels, and even then there are friendly kills?
FC1 was a turkey shoot. You could just make multiple passes until everything was dead. In real life you are going to make a single pass, and then you are going to wait for recon data from another flight or the ground to determine the damage you did.
I applaud the devs for making it harder. Now if there was better ground vegetation and the ground AI took evasive maneuvers.
IMO if you want it easy, use labels, arcade mode, or get Ace Combat.