The cause of much of charter travel delay and disruption is the resort changeover day concept of the fixed 1 or 2 week break which requires a large number of flights to converge on the destination airport on the same day creating congestion both on the ramp and in the terminal as the flights are timed to arrive in order to deliver passengers to the buses which then head out to the resorts having just brought the inbound passengers from the resorts.
This puts pressure on the airports in terms of check in, baggage handling, security, ramp handling and also ATC both at the airport in terms of parking and runway slots and also en-route. Personally, I think the way ahead is to do away with changeover day altogether and sell more bespoke holidays using the scheduled airlines. (and get rid of the night flights)