6 mile gap means a departure can go in between arrivals
the layout of edi means there is little scope for packing aircraft on the basis that tower can tell approach when they want a gap - all that would happen is the dep would have to wait for the ones already committed to the approach to land til he could depart - and dont tell me you'd be happy with that either
and by not adhering to the speed put on by app - you're being less than helpful
re the holding - as edi doesnt have the last few levels in the hold - sometimes trying to get the aircraft from scottish can be a work of art which may be why there were big gaps -
or maybe there was something else going on at the time which you were not aware of
as gonzo says - go and have a look for a few hours and have a listen in at a busy time of the day - ie around half eight til just after ten at night - or maybe the morning rush bit and then you can make your whines
ps - just because no one comments on the fact you havent flown the instructed speed doesnt mean it hasnt been noticed - if you fly faster - never noticed that the departure at the hold doesnt go because the gap has disappeared because you are unable to follow an instruction? ( note instruction and not a request!)