That's a hard one to answer Kanok and greatly depends on routes, state of economies etc. The old model of full service on short haul has seen its day I think, why should I fly KLM, BA or LH to AMS or any other near destination when all I get for the extra price is a buttie and coffee? That assumes that the Loco has a good price.
Pax have become more savvie and book ahead, the small impromptu market will always suffer the penalty of higher price shortly before flying and maybe full service will offer better price. However, that is only short haul.
Whether LCCs can open up the longer haul market remains to be seen, it is a far different market and the corpses are there to see, Laker, Zoom etc.
I do not think the present bunch of Locos will find the magic formula but do not rule out a true business visionary coming along to do so.