Last summer the presence of so many non-based aircraft operating routes seemed to spread the arrivals/departures load a bit more evenly throughout the day.
I assume you mean the total number of arrivals/departures. If you look at the Ryanair schedules alone from Summer 2013 they were horrifically peaky with sometimes almost 5 or 6 hours with no flights through the afternoon then nearly half the day's flights between around 7:30 and 9:00 in the evening!