Use real cutlery as disposable cutlery is not sustainable, not even wood.

In small airports, like Vigra, where there only 1 or 2 airplanes stand, have roofs like carports to prevent snow on plane. This will reduce amount of deicing fluid needed.

Award additional EuroBonus bonus and/or level points when renting an electric vehicle through a car rental partner such as Hertz, Avis or Sixt.

Keep the temperature at decent levels instead of heating too much in air.

Do not carry tax-free goods on flights. Use as online service and if necessary in partnership with partners allowing pick-up at airports.

I would use my skills in optimization and deep learning to learn what frequenzies and time schedules that maximizes the load factor of each aircraft in the fleet.