Air India - Depressing
Look, Air India isn't a real commercial enterprise as we would understand it. It is a political football kicked around between the Congress Party and the BJP, whichever party has the office of Prime Minister at the time.
Were it to be truly commercial, and free from political pressure, some of the first routes to be chopped would be from Ahmedabad..., but wait, said city is the home of one Mr. Modi, who has recently become Prime Minister; so that won't happen.
Routes to the USA perform badly, but will they chop those politically prestigious routes...no, the politicians won't let them.
Biggest threat to the BHX (and the other - majority - loss making routes) would be if Air India was a truly commercial business, and that, given Indian politics, isn't going to happen any time soon.