<<As far as departures,I suppose that if traffic is heading north it would be of use,but it still would have to be integrated with the other runways.Has this been considered from an ATC point of view.Somehow I doubt it.>>
No problems.. Once staff are properly trained it will become second nature - that's what ATCOs do. We used to run three, or even 4 runways, occasionally at Heathrow before they were converted to parking areas, eg 27R to take off, 23L and 27L for landing. No problems; in fact it would be much easier with all runways facing the same direction.
I just wonder about that little RAF airstrip - Northolt!!