I believe the darbar system is fair. I think it mimics the multiple warning sources employed during the war. They had ground observers, observers on ships, some radar, and inflight observers that would give basically the same information we get, that aircraft are in a given area. Maybe there was more information than what we get, not less. They would probably have known the altitude of the aircraft, the type and the direction also. Even with the darbar system we have, it's not exacly easy to be in the right place, at the right time, with the right aircraft for interception. This darbar system, remember, also gives bombers information about approaching enemy aircraft making it difficult to really sneak up on bombers with interceptors.
I know I am mainly a fighterpuke now but I have done alot of bombing in the past and I never thought the system was unfair then. If I may humbly suggest, bomber pilots could learn alot about how to survive an interception by flying interception's them selves. Conversly, fighter pilots who want to learn bomber interception will learn alot by flying a bomber and observing what makes a good interception.
I see alot of posts that are really asking to make the game easier and I understand, that as a new guy there is alot to learn and a price to pay for that education. After you have "learned" the different aspects of the game, then it is the challenge of using those skills in a difficult game that has a reward for excellence.