Buster I have no doubt that there are some folks who will pay for a premium service but - enough to fill a schedule? I, for one, never doubted that Silver/Max/Eos would work. The template was established and proven by LH out of DUS (I think they were the first) and I am sure that this kind of carrier will continue to fill their a/c. In due course, there will be mergers but the category of travel will be around unless there is a truly considerable upset in the world.
The truly rich folks who have houses on the Spanish islands tend to go in their own a/c or boats, or shared/part ownership or even personal charter. Not forgetting that many legacy carriers still operate a biz service to these destination, which is what I think that those who will pay the extra for a special trip are too few and far between for a schedule.
If they wanted to start premium biz medium/long haul heading East from the UK, then they would take a market sector that has been set up by Silver/Max/Eos before those carriers can expand Eastwards themselves. But to play about in the Med????