Im not sure of the frequency of flights in and out of Ed but I can see the flightpath along the Firth Of Forth from my office window in town and the spacing would sometimes be a bit tight to get in with a light single whilst complying with wake clearances between the heavies.
Perhaps slot times for GA wouldn`t be a bad thing but a bit restrictive for any training ops.
With so many other fields around the Central Belt I do wonder what the appeal is to operate from Ed. Could it be the licensing, Fife being the nearest alternative?