You should try driving airside at peak times trying to cross the taxiways. Its frequently possible to have to wait 15-20 mins at the crossing points due to movements at peak times (mainly pushbacks) This obviously has a knock-on for the drivers and the services affected.
Its getting close to the stage where any further expansion of stands at LTN will be negated by the limited taxiway layout and lack of dual taxiways on areas such as the East Apron (where aircraft are often delayed having to wait for another aircraft to push or arrive)