Option to remove included luggage when booking. This will help SAS to predict load and be more efficient.

Replacing the paper catalog with a QR code sticker. This saves tons of paper. Many catalogs are destroyed or unread.

Charging mobile phones or other equipment from sunlight in the sky. «Day flights are always sunny»

A lot of ground equipment is still driven by internal combustion engines, and can be upgraded to run on electric instead for better efficiency.

Implement the potential to offset carbon footprint by CDR technologies like enhanced rock weathering;

Instead of serving main meals on the flight briefly after takeoff, service the meal in the boarding area. Save load, effort and waste.