I use long haul out of EMA all the time - only thing is it's all freight!!
I'm not sure there is a demand for dedicated long haul, although I would say an Emirates style operation (using a transit hub) may well be sustainable.
On a trip last month (BHX/Perth) the Emirates driver commented about how many people thay pick up from my area (Coalville), so I get the impression that there's a lot of us East Midlander's travelling to BHX to catch a long haul flight. So it's probably a feasable proposition, although I don't actually see it happening, certainly not in the near future.