Earn EuroBonus points when recycling. Collaborate with apps such as Bower and Repeat in Sweden. They offer cash rewards for recycling. Why not reward points instead!

Reusable boarding cards for people without phones. Like the consius travelee bag tag.

Include 1 free unit of biofuel per booked flight, for passengers that have reached Conscious Traveller status.

When I am flexible for when to fly, I would be open to SAS selecting the actual flight, getting to fewer, fuller flights.

Implement sharkskin technology or (my own) coating to reduce air resistance and micro-drag from the fuselage.

For every mile the aircraft flies overseas, SAS commits to a certain amount of plastic being removed from that ocean.