Why not, for instance, multiply air tax on traffic being diverted out of the U.K. regions over other EU airports in order to help offset a tax break to the industry - both domestic and international - at airports inside the U.K.??
Oops sorry - that would require a thought wave to drift north of the Watford Gap. Silly Me! ....
Because if you did that, other countries would as well and cripple LHR. "forcing" airlines into such decisions will not result in a load of direct routes appearing. The consumer would just suffer and any influx of direct routes will go to LHR anyway if it was to happen.
TCX and eventually DY will be the dominant carriers at MAN in time. Hard to predict what VS will in terms of high freq services such as current JFK/ATL etc.
DUB may take traffic, but from what I gather the majority of UK transit is out of LHR. EDI has saw major growth in US traffic in recent years and EI also move big numbers out of EDI.
Perhaps if Manchester (city) and N West were more proactive in terms of tourism promotion like Scotland and Ireland are which will play a major role in ensuring US direct routes. It's tourists who fill a massive amount of capacity out of Ireland and Scotland and even London.