Perhaps at least one long haul direct (Mumbai or Delhi) might work?
It's not "what might work", and this example is fairly unlikely given VS just dropped LHR-BOM which fed onto exisiting US flights, of which EDI has no VS or DL long haul. Imagine the scenario where a code sharing, revenue sharing DL/VS transatlantic joint venture is deciding where to place their new multi million $ Boeings. Scotland-India would be so far off the list as to be off the page as it's not a core market or even part of the JV, added to the fact that Edinburgh doesn't have much of an Indian community.