A complicating factor is that of origin-destination control ("O&D control"). Someone purchasing a ticket from Melbourne to Sydney (as an example) for A$200 is competing with someone else who wants to fly Melbourne to Los Angeles through Sydney on the same flight, and who is willing to pay A$1400. Should the airline prefer the $1400 passenger, or the $200 passenger plus a possible Sydney-Los Angeles passenger willing to pay $1300? Airlines have to make hundreds of thousands of similar pricing decisions daily.
In the 1990s, "open skies" agreements became more common. These agreements take many of these regulatory powers from state governments and open up international routes to further competition. Open skies agreements have met some criticism, particularly within the European Union, whose airlines would be at a comparative disadvantage with the United States' because of cabotage restrictions.
In view of the congestion apparent at many international airports, the ownership of slots at certain airports (the right to take-off or land an aircraft at a particular time of day or night) has become a significant tradable asset for many airlines. Clearly take-off slots at popular times of the day can be critical in attracting the more profitable business traveler to a given airline's flight and in establishing a competitive advantage against a competing airline.
Chania is a great choice. A wonderful charming town. Elounda is great for a quiet laid back stop, Agios Nikolaos has a more interesting vibe and is more of a real town. Also very charming. I prefer Ag Nik but Elounda has more luxurious hotels. (Crete hotels.) Naxos has lots to see in the interior so if you didn’t explore then certainly consider that. Folegandros and Milos are both incredible. Folegandros is more suited to walking and relaxing (and has some top notch restaurants and hotels). On Milos you need to do a tour and get out and actively explore to do it justice. Geologically Milos is stunning. A little like Santorini but with better beaches.
We are planning to come back at the start of September for 2 weeks to visit different islands for some beach and sun. To give you some background, we loved Santorini, Milos and the quieter / smaller places in Crete (Loutro, Falassarna, Samaria Gorge). We enjoy beach time, some hiking, site seeing, good wine / food and good / buzzy atmosphere at night for dinner / tavernas.
It’s best to visit Greek islands within the same group. For example, I wouldn’t recommend visiting Corfu and Santorini on the same trip as they’re on opposite sides of the country. Instead, visit islands in the same island group: the Cyclades, the Sporades, the Dodecanese, the Ionian, the Saronic, and the Northeastern Aegean. For one, they’re close to each other. And two, they have frequent ferry connections with each other. For first time visitors to Greece, the Cyclades make the most natural and convenient introduction.