Actually I think some unexpected routes might be very profitable. I heard for example for BA, some route in West Africa (forgot which one) used to be very profitable due to almost no competition and an almost all-business-traveller demand.

So I could expect for CX, probably JFK/LAX are not necessarily the most profitable. I have the feeling many Japan routes are very expensive for the distance, could probably very profitable. Sometimes, a return Y fare HKG - TYO is about the same as HKG - SYD. Similarly, I could imagine JNB probably works quite well.